Level – 2 Exercise – 3

Interest
No. of Question: 25 Time : 20 Min
M
(c) Rs. 1040 in fixed rate
1. Divide Rs. 7806 between A and B, so that A's share
at the end of 9 years is equal to B's share the end
(d) Rs. 350 in floating rate
of 11 years, compound interest being at 4
percentage?
3. Rs. 4500 is invested at 8% p.a. on simple interest.
If that interest is added to the principal after every
7806 :- dks A rFkk B ds chp bl izdkj ck¡Vs fd 9 o"kZ
10 years, the amount will become Rs. 15,000
ds vUr esa A dk fgLlk] 11 o"kZ ds vUr esa B ds fgLls
after?
ds cjkcj gks] tcfd pØo`f) C;kt nj 4 izfr'kr gksA
4500 :Ik;s 8 izfr'kr lk/kkj.k C;kt nj ij fuos'k fd;s
(a) Rs 4036 and Rs 3770
tkrs gSA ;fn izR;sd 10 o"kZ i'pkr~ C;kt dks ewy/ku esa
tksM+k tkrk gS rks fdrus o"kZ Ik'pkr~ jkf'k 15]000 gks
(b) Rs 4056 and Rs 3750
tk;sxh\
(c) Rs 4016 and Rs 3790
(a) 15.8 years (b) 25 years
(d) Rs 4076 and Rs 3730
(c) 14.6 years (d) 20.36 years

2. James has applied for a loan of Rs. 200,000. He has 4. If Rs. 8,700 amounts to Rs. 12,528 at compound
two options, the first is a fixed compound interest interest in a certain time, then Rs. 8700 amounts
of 15% for 3 years and the other is a floating to what in half of the time?
compound rate of 20% for first year, 15% for the
;fn 8700 :i;s ,d fuf’pr le; esa pØo`f) C;kt
second year and 10% for the third year. If he
repays the loan after 3 years, then which option is
ij 12528 :i;s gks tkrs gS rks 8700 :i;s blds vk/ks
beneficial to James and by how much? le; esa fdrus gks tk;sx
a s\
(a) Rs. 9640 (b) Rs. 10,440
tsEl us 2]00]000 :- ds _.k ds fy;s vkosnu fd;kA
(c) Rs. 9800 (d) Rs. 10,614
mlds ikl nks fodYi gS ,d 3 o"kksaZ ds fy;s 15
izfr'kr dh fuf'pr pØo`f) C;kt nj rFkk nwljh
vLFkkbZ pØo`f) C;kt nj gS tks izFke o"kZ ds fy;s 20 5. If a certain sum of money amounts to Rs. 5100 in 7
izfr'kr] nwljs o"kZ ds fy, 15 izfr'kr vkSj rhljs o"kZ ds years and Rs. 7650 in 14 years at compound
fy;s 10 izfr'kr gSA ;fn og rhu o"kZ i'pkr~ _.k interest rate, then find principal?
pqdkrk gS rks tsEl ds fy;s dkSulk fodYi Qk;nsena gS ;fn dksbZ /ku pØo`f) C;kt dh nj ij 7 o"kZ esa
rFkk fdruk\ 5,100:- rFkk 14 o"kZ esa 7,650: gks tkrk gS rks og /ku
Kkr djsaA
(a) Rs. 895 in fixed rate
(a) Rs. 3570 (b) Rs. 3740
(b) Rs. 575 in floating rate
(c) Rs. 3400 (d) Rs. 3100
 sum of Rs. 1000.

6. The difference between the simple interest ;fn lk/kkj.k C;kt 10.5% okf"kZd gS vkSj pØo`f)
received from two different sources on Rs. 1500 C;kt 10% okf"kZd gS] r¨ 1000 # ij 3 o"kZ ds ckn
for 3 years is Rs. 13.50. The difference between C;ktksa esa varj Kkr djks A
their rates of interest is:
(a) Rs. 15 (b) Rs. 12
1500 #i;s ij 3 lky ds fy, n¨ vyx&vyx lz¨r¨a
(c) Rs. 16 (d) Rs. 11
ls çkIr lk/kkj.k C;kt ds chp dk varj 13-50 #i;s gS
mudh C;kt nj¨a ds chp dk varj gS
(a) 0.1% (b) 0.2%

(c) 0.3% (d) 0.4% 10. James gave Rs. 1200 on loan. Some amount he
gave at 4% per annum on simple interest and
remaining at 5% per annum on simple interest.
7. A person invested in all Rs. 2600 at 4%, 6% and After two years, he got Rs. 110 as interest. Then
8% per annum simple interest. At the end of the the amounts give at 4% and 5% per annum on
year, he got the same interest in all the three simple interest are, respectively
cases. The money invested at 4%
tsEl us 1200# y¨u ij fn;sA dqN jkf'k mlus 4%
,d O;fDr us 2600 #i;s 4%] 6% vkSj 8% çfr o"kZ çfr o"kZ lk/kkj.k C;kt ij vkSj 'ks"k 5% çfr o"kZ
lk/kkj.k C;kt ij fuos'k fd;kA o"kZ ds var esa] mlssa lk/kkj.k C;kt dh nj ls nhA n¨ lky ds ckn] mls
rhu¨a fLFkfr;¨a esa leku C;kt feyhA 4% ij fuos'k 110 # C;kt ds :i esa izkIr gq,A rc jkf'k;k¡ tks
fd;k x;k /ku gS lk/kkj.k C;kt ij Øe'k% 4% vkSj 5% çfr o"kZ nh
(a) Rs. 200 (b) Rs. 600 tkrh gSa gksx
a h\

(c) Rs. 800 (d) Rs. 1200 (a) Rs. 500, Rs. 700

(b) Rs. 400, Rs. 800

8. James invested a sum of money at a certain rate of (c) Rs. 900, Rs. 300
simple interest for a period of 4 yrs, If he invested (d) Rs. 1100, Rs. 1100
sum of money for 6 year then the total interest
earned by him would have been 50% more than
the earlier interest amount. What was the rate of 11. The compound interest on a certain sum for 2
interest per cent per annum? years at 10% per annum is Rs. 1260. The simple
tsEl us 4 lky dh vof/k ds fy, lk/kkj.k C;kt dh interest on the same sum for double the time at
,d fuf'pr nj ij /kujkf'k dk fuos'k fd;k] ;fn og half the rate per cent per annum is
/kujkf’k dks 6 o"kZ ds fy, fdlh nj ij fuos’k djrk rks
10% çfr o"kZ ij 2 o"k¨Za ds fy, ,d fuf'pr jkf'k ij
mlds }kjk vftZr dqy C;kt igys dh C;kt jkf'k ls
50% vf/kd g¨xkA çfr o"kZ C;kt nj D;k Fkh\ pØo`f) C;kt # 1260 gS blh jkf'k ij lk/kkj.k C;kt]
nks xquk le; vkSj çfro"kZ vk/kh nj ls gS
(a) 4 (b) 8

(c) 5 (d) Cannot be determined (a) Rs. 1200 (b) Rs. 1160

(c) Rs. 1208 (d) Rs. 1175

9. If the simple interest is 10.5% annual and

compound interest is 10% annul, find the
difference between the interests after 3 years on a 12. The simple interest on a sum of money will be Rs.
 300 after 5 years. For the next 5 years principal is If the time period is increased by 2 years, the
tripled, what will be the total interest at the end of simple interest on the same sum increases by Rs.
the 10th year ? 180. The sum is :

,d jkf'k ij 5 lky ckn lk/kkj.k C;kt # 300 gSA ;fn nj 2% c<+ tkrh gS] r¨ /kujkf'k ij çkIr lk/kkj.k
vxys 5 o"k¨Za ds fy, ewy/ku d¨ rhu xq.kk dj fn;k C;kt 108 #i;s ls c<+ tkrk gSA ;fn le;kof/k 2 o"kZ
tkrk gS] 10 osa o"kZ ds var esa dqy C;kt D;k g¨xk\ c<+ tkrh gS] r¨ leku jkf'k ij lk/kkj.k C;kt 180

(a) 1200 (b) 900

#i;s c< tkrk gS jkf'k gS

(c) 600 (d) 1500 (a) Rs. 1800 (b) Rs. 3600

(c) Rs. 5400 (d) Date inadequate

13. A person lent a certain sum of money at 4%

simple interest; and in 8 years the interest 16. Bond deposited two parts of a sum of Rs. 25,000 in
amounted to Rs. 340 less than the sum lent. Find different banks at the rates of 15% per annum and
the sum lent. 18% per annum respectively. In one year he got

,d O;fDr us 4% lk/kkj.k C;kt ij ,d fuf'pr jkf'k Rs. 4050 as the total interest. What was the
amount deposited at the rate of 18% per annum?
m/kkj yh( vkSj 8 o"k¨Za esa C;kt m/kkj jkf’k ls # 340
de gks tkrk gS rks m/kkj jkf'k dk irk yxk,aA c‚UM us 25]000 #i;s ds n¨ Hkkx¨a d¨ fofHkUu cSad¨a esa
Øe’k% 15% çfro"kZ vkSj 18% çfro"kZ dh nj ls tek
(a) 500 (b) 600
fd;kA ,d o"kZ esa mUgsa 4050 # dqy C;kt ds :i esa
(c) 1000 (d) 1500
izkIr gq, 18% çfr o"kZ dh nj ls tek dh xà jkf'k
D;k Fkh\
14. Simple interest on a certain amount is of the (a) Rs. 9000 (b) Rs. 18000
principal. If the numbers representing the rate of (c) Rs. 15000 (d) Rs. 10000
interest in percent and time in years be equal,
then time, for which the principal is lent out, is
17. Bond invested an amount for 2 years at 15 percent
,d fuf'pr jkf'k ij lk/kkj.k C;kt ewy/ku dk 9@16
per annum at simple interest. Had the interest
gSA ;fn C;kt dh nj çfr'kr vkSj le; o"k¨Za esa dk
been compounded, he would have earned Rs.
çfrfuf/kRo djus okyh la[;k cjkcj g¨] r¨ le;]
450/- more as interest. What was the amount
ftlds fy, ewy/ku fn;k x;k gS] gksxk \
invested?

(a) 5 years (b) 6 years c‚UM us ,d jkf'k dk lk/kkj.k C;kt ij 2 lky ds fy,
15 çfr'kr çfr o"kZ dh nj ls fuos'k fd;kA vxj C;kt
(c) 7 years (d) 7 years
pØo`f) g¨rk] r¨ og # 450 C;kt ds :i esa vf/kd
izkIr djrk gS fuos'k dh xà jkf'k D;k Fkh\
15. If the rate increases by 2%, the simple interest
(a) Rs. 22000 (b) Rs. 24000
received on a sum of money increases by Rs. 108.
(c) Rs. 25000 (d) Rs. 20000
 20. Two equal sums of money were invested, one at
4% and the other at 4.5%. at the end of 7 years,
18. Bond invested money in two schemes A and B,
the simple interest received from the latter
offering compound interest at 8 percent per
exceeded to that received from the former by Rs.
annum and 10 percent per annum respectively. If
31.50. Each sum was
the total amount of interest accrued through the
two schemes together in two years was Rs. n¨ leku jde dk fuos'k fd;k x;k] ,d 4% ij vkSj
5078.70 and the total amount invested was Rs. nwljk 4-5% ijA 7 o"kksZa ds var esa] nwljh jde ls
27,000, what was the amount invested in Scheme feyus okyk lk/kkj.k C;kt igyh ls çkIr C;kt ls 31-
A? 50 # vf/kd g¨ x;kA çR;sd jkf'k Fkh
c‚UM us n¨ ;¨tukvksa A vkSj B esa Øe'k% 8 çfr'kr çfr (a) Rs. 1200 (b) Rs. 600
o"kZ vkSj 10 çfr'kr çfr o"kZ dh nj ls pØo`f) C;kt
(c) Rs. 750 (d) Rs.900
dh nj ls iSlk yxk;k A ;fn n¨ o"kksZa esa ,d lkFk n¨uksa
;¨tukvksa ds ek/;e ls vftZr dqy C;kt 5078-70 #
vkSj fuos'k dh xà dqy jkf'k 27]000# gS rks Ldhe A 21. Alice invested an amount of Rs. 16,000 for two
esa fuos'k dh xà jkf'k D;k Fkh\ years on compound interest and received an
amount of Rs. 17,640 on maturity. What is the rate
(a) Rs. 15,000 (b) Rs. 12,500
of interest?
(c) Rs. 13,500 (d) Cannot be determined
,fyl us 16]000 # dh jkf'k dk fuos'k n¨ lky ds
fy, pØo`f) C;kt ij fd;kA vkSj ifjiDork ij
19. James invested an amount of Rs. 12,000 at the 17]640 # dh jkf'k çkIr dhA C;kt nj D;k gS\
simple interest rate of 10 percent per annum and
(a) 5% pa (b) 8%pa
another amount at the simple interest rate of 20
percent per annum. The total interest earned at (c) 4% pa (d) Date inadequate

the end of one year on the total amount invested

became 14 percent per annum. Find the total
22. A finance company declares that, at a certain
amount invested.
compound interest rate, a sum of money
tsEl us 12]000 # dh jkf'k 10 çfr'kr çfr o"kZ dh deposited by anyone will become 8 times in three
lk/kkj.k C;kt nj ij vkSj nwljh jkf'k dks 20 çfr'kr years. If the same amount is deposited at the same
okf"kZd lk/kkj.k C;kt dh nj ij fuos'k fd;kA dqy compound rate of interest, then in how many year
jkf'k ij ,d o"kZ ds var esa vftZr dqy C;kt çfr o"kZ will it become 16 times ?

14 çfr'kr g¨ x;kA fuos'k dh xà dqy jkf'k Kkr ,d foÙk daiuh ;g ?k¨"k.kk djrh gS fd ,d fuf'pr
dhft,A pØo`f) C;kt nj ij] fdlh ds }kjk tek fd;k x;k
(a) Rs. 22,000 (b) Rs. 25,000 /ku rhu o"kkZsa esa 8 xquk g¨ tk,xkA ;fn mlh jkf'k d¨
leku pØo`f) nj ij tek fd;k tkrk gS] r¨ fdrus
(c) Rs. 20,000 (d) Rs. 24,000
o"kksaZ esa ;g 16 xquk g¨ tk,xh\

(a) 5 years (b) 4 years

 (c) 6 years (d)7 years (c) Rs. 14,000 (d) Rs. 21,000

Answer Key
1 b 2 b 3 d 4 b 5 c
23. Two friends A and B jointly invested Rs. 81,600 at
6 c 7 d 8 d 9 c 10 a
4% per annum compound interest. After 2 years A 11 a 12 a 13 a 14 d 15 d
gets the same amount as B gets after 3 years. The 16 d 17 d 18 c 19 c 20 d
21 a 22 b 23 a 24 a 25 d
investment made by B was

n¨ n¨Lr¨a A vkSj B us la;qDr :i ls 81600 # 4%

çfr o"kZ pØo`f) C;kt ij dh nj ls fuos’k fd;k A 2 Solutions
lky ckn A d¨ mruh gh jkf'k feyrh gS ftruh B d¨ 1. (b)
3 lky ckn feyrh gSA B }kjk fd;k x;k fuos'k Fkk
Let A's and B's present share be Rs A and Rs B.
(a) Rs. 40,000 (b) Rs. 30,000
Rate = 4%
(c) Rs. 45,000 (d) Rs.38,000
Now,

24. The simple interest on a sum of money is th of the  4 

9
 4 
11

A 1   = B 1  
 100   100 
principal, and the number of years is equal to the
rate per cent per annum. Find the rate percent.
9 11
 104   104 
 A  = B 
,d /kujkf'k ij lk/kkj.k C;kt ewy/ku dk 1@9 oka  100   100 
g¨rk gS] vkSj o"k¨Za dh la[;k nj çfr'kr çfr o"kZ ds
2 2
cjkcj g¨rh gSA nj çfr'kr Kkr djsaA A  104   26  676
 =  =  =
B  100   25  625
(a) 3 % (b) 3%
⇒ A : B = 676 : 625
(c) 10% (d) None of these
 Share of A = Rs. 4056

25. Sam invested money in two schemes A and B

And Share of B = Rs. 3750
offering Simple interest at 8 percent per annum
and 13 percent per annum respectively. If the total 2. (b)
amount of interest accrued through the two
schemes in two years was Rs. 7700 and the total At fixed rate of 15% compounded annually
amount invested was Rs. 35,000. What was the
amount invested in scheme B. 3
 15 
Amount = 200,000  1  
lSe us nks Ldhe A rFkk B esa Øe'k% 8% okf"kZd rFkk 13%  100 
okf"kZd lk/kkj.k C;kt ij /ku fuos'k fd;kA nksuksa Ldheksa
ls nks lkyksa esa izkIr dqy C;kt 7700 :i;s gS rFkk = 200,000×
23 23 23
× ×
fuos'k fd;k x;k dqy /ku 35,000 :i;s gSA Ldhe B esa 20 20 20

fuos'k fd;k x;k /ku fdruk gS\

= Rs. 304,175
(a) Rs. 15,750 (b) Rs. 19,250
 At floating rate of 20%, 15% and 10% Amount = = 8,700 × 1.2 = Rs. 10,440
6 23 11
200,000× × ×
5 20 10
5. (c)
= Rs. 303,600 Let the principal be Rs. P and rate be x
14
So difference = 304,175 – 303,600 = Rs. 575  r 
P 1 
100  7650
∴  7

So at floating rate of interest James is paying Rs.  r  5100
P 1  
575 less.  100 

7
3. (d)  r  3
⇒ 1  
 100  2
Principal = 4500
Now

4500  8  10  r 
7
Amount after 10 year =4500+ P 1 
100
100  = 5100
 

= 4500 +3600 = Rs. 8100 3

⇒P× = 5100
2
8100  8  10
Amount after 20 years = 8100+ = ⇒ P = Rs. 3400
100
8100+6480 = Rs. 14580 Alternate:

P 
7 year
5100 
7 year
7650
Remaining interest = 15000 – 1458 = Rs. 420
5100  5100
P= = 3400
14580  8  x 7650
 420 =
100

420  100 6. (c)

x= = 0.36 years
14580  8
( )–( ) = 13.50

 Amount will become 15000 after 20.36 years. ⇒ 4500 (R1 – R2) = 1350 ⇒ R1 – R2 = = 0.3%

Alternate:

4. (b) Difference between simple interest for 3 year =

13.50
let rate = R % and time = n years
13.50
Then 12528 = 8700 ( ) For one year = = Rs. 4.5
3

⇒ =( ) 4.5
Difference between Rate% = ×100 = 0.3%
1500
⇒ 1.44 = ( )

⇒( ) =√ = 1.2 7. (d)

Let the parts be x, y and [2600 - (x + y)]. Then,

Required amount for year = 8,700( )
 [ ( )] Comuned interest on 1000 for 3 year at 10% p.a.
= =
11 11 11
∴ = = or y = x. = 1000× × × - 1000
10 10 10
( )
So, = = 1331 – 1000 = 331

( ) Simple interest on 1000 for 3 year at 10.5% p.a.

⇒ 4x = ⇒ 52x = (7800 × 8)
1000  10.5  3
⇒x=( ) = 1200. SI = = 315
100

∴ Money invested at 4% = Rs. 1200. Difference = 331 – 315 = Rs. 16

Alternate: 10. (a)
Assume he invested A : B : C Let the amount given 4% per annum be Rs. x.

A 4  1 B  6  1 C  8  1 Then, amount given at 5% per annum = Rs. (1200

Then = =
100 100 100 - x)
( )
4A = 6B = 8C Now, + = 110
⇒ A : B : C = total ⇒ x = Rs. 500
⇒ 6 : 4 : 3 = 13 And, the amount given at 5% per annum = Rs.
Amount invested ate 4% is (1200 - x) = Rs. (1200 - 500) = Rs. 700

2600 11. (a)

A= ×6 = 1200
13
Let the sum be Rs. P. Then,
8. (d)
⇒ [P( ) - P] = 1260
For T = 4 years, P = P and R = R% per annum

S.I. = = Rs. ( ) = Rs. ( ) ⇒ [P( ) -1] = 1260

For T = 6 years, P = P and R = R% per annum ∴ Sum = Rs. 6000

S.I. = = Rs. ( ) = Rs. ( ) So, S.I. = Rs. ( ) = Rs. 1200

Now, 150% of Alternate:

1. Assume principal = 100
⇒ × ⇒R=x
100
So, the given data is insufficient to find the rate of
interest per cent per annum. 10 10

9. (c) 1
At 10% compound interest the interest in 3 years
would be 33.1% = Rs. 331 According to question = 21 = 1260

At 10.5% simple interest the interest in 3 years  1 = 60

would be 31.5% = Rs. 315 So principal = 100×60 = 6000
Difference = Rs. 16 6000  4  5
S.I. = = 1200
Alternate: 100
12. (a) ( )
[ ]–( ) = 180

Simple interest for 5 years = Rs. 300

⇔ 2xR = 18000 … (ii)
Now, when principal is trebled, the simple interest
Clearly, from (i) and (ii), we cannot find the value
for 5 years will also treble the simple interest on
of x.
original principal for the same period. Thus, S.I.
So, the data is inadequate.
for last 5 years when principal is trebled.
16. (d)
= 3 × 300 = Rs. 900
Let the amount deposited at the rate of 15% per
∴ Total SI for 10 years = 300 + 900 = Rs. 1200
annum be Rs. x.

15% of x + 18% of (25000 - x) = 4050

13. (a)
or, 15% of x + 18% of 25000 – 18% of x = 4050
Let the sum be Rs. x.
or, 3% of x = 4500 – 4050 = 450 ⇒ x = Rs. 15000
∴ Interest = =
Amount deposited at 18%

= (25000 – 15000) = Rs. 10000

32x+34000=100x Alternate:

68x=34000 Total interest = 4050

x=500 Principal = 25000

Direct Formula 4050 5 1

Rate % = ×100 = 16 = 16 %
25000 25 5
Sum = × 340 = = Rs. 500
15% 18%
14. (d)
1
16 %
Let sum = x. Then, S.I. = x. 5

Let rate = R% and time = R years. 4 1

1 1
5 5
∴( )= ⇔ R2 =
9 : 6=3:2
⇔R= =7 .

25000
Hence, time = 7 years. So amount deposit on 18% = ×2 = 10000
5
15. (d)
17. (d)
Let the sum be Rs. x, rate be R% p.a. and time be T
+ 450 = [P (1 + ) - P]
years.

( ) ⇒ P = Rs. 20,000.
Then, [ ]–( ) = 108

⇔ 2xT = 10800 … (i)

 3 So amount invested in scheme A
R = 15% =
20
27000
=  1 = Rs. 13500
T = 2 year 11

Assume = Principal = 400 19. (c)

400 Let the amount invested at 20% rate be Rs. x,

According to the question,
60 60
12000× + x× = (12000 + x) ×
9
or, 1200+ = 1680+ x
He get Rs. 9 extra on 400 Principal According to
question or, - x= 480

9 = 450 or, x = 480

1 = 50
x = Rs. 8000
So Principal = 400×50 = Rs. 2000
Total amount invested Rs. = (12000 + 8000) = Rs.
18. (c) 20000

Assume he invested Rs. A and B respectively in Alternate:

scheme A and Scheme B.
10% 20%
Total Principal P = Rs. 27000
14%
Total interest = Rs. 5078.70
6 4
Total amount in two year = 27000+5078.70
3 : 2
2
 R 
A = P 1 
 100  According to question 3 = 12000

1 = 4000
 R  32078.70
 1  100   27000
  So amount invested on 20% = 4000×2 = 8000

 R  11881 Total amount invested Rs. = 12000+8000 = 20000

 1  100   10000
 

 R   109  20. (d)

 1  100    100 
   
Difference of S.I. = Rs. 31.50
=R=9%
Let each sum be Rs. x. Then
8% 10%
– = 31.50
9%

1 : 1 or × =
 or x = Rs. 900 Given 8P = P (1 + )3

Alternate: Where P = Principal amount,

If principal and time is same then difference in r = compound interest rate
interest is equal to difference in Rate %
⇒ r = 100%
So → 0.5×7 = 31.50
∴ let the time in which the principal amount
315 becomes 16 times be n
1=
5 7
Then 16P = P (1 + )
1=9
⇒ 16 = 2n ⇒ n = 4yrs.
So Principal = 100×9 = 900
23. (a)

Let A lent Rs. x and B lent Rs. y

21. (a)
Since, A and B together lent out Rs. 81600
Amount = Rs. 17640, Principal = Rs. 16000
∴ x + y = 81,600
Time = 2 yrs, Rate = R
Now, given (r) rate = 4%
17640 = 16000 (1 + )2
∴1+r=1+ =
⇒ = (1 + )2 ⇒ 1.1025 = (1 + )2
According to the question, we have
⇒1+ = 1.05 ⇒ = 1.05 – 1 = 0.05
=( ) =
⇒ R = 5%
∴ Investment made by B = 81600 × = 40,000
Alternate:

T
Alternate :
 R 
A = P 1  
 100  Assume A and B invest respectively A and B rupee

2 3
 R 
2
 4   4 
17640 = 16000  1  A 1    B1  
100   100   100 
 

A 104 A 26
 R  17640   
 1  100   16000 B 100 B 25
 
81600
 R  21 Investment by B = ×25 = 40000
 1  100   20 51
 
24. (a)
1
Rate % = ×100 = 5%
20 Let principal = P, time years, rate = t

Then, =

22. (b)
∴ t2 = ∴t= =3
 ∴ rate = 3 %

Direct formula:

Rate = time = √ = =3 %

25. (d)

Total interest = Rs. 7,700

Total sum = Rs. 35,000

7700  100
Effective rate = = 11%
35000  2

Now

A B

8% 13%

11%

2 3

Ratio of investment in A and B = 2 : 3

3
∴ Sum invested in scheme B = × 35,000 = Rs.
5
21,000