O LEVEL (P1)
SIGNIFICIANT
FIGURES
QUESTION'S
1
1 Complete the statements in the answer spaces.
Answer (a) 4872 correct to 1 significant figure is ......................... [1]
(b) 4872 correct to ................. significant figures is 4870. [1]
2 By writing each number correct to 1 significant figure, estimate the value of
8.62 × 2.042 .
_____________
0.285
Answer ..................................................[2]
3 A basketball stadium has 13 492 seats.
During a season a basketball team played 26 matches and every seat was sold for each match.
At each match a seat costs $18.80.
By writing each value correct to 1 significant figure, estimate the total amount of money
paid to watch these matches during the season.
Answer $ ...............................................[2]
4 By writing each number correct to 1 significant figure, estimate the value of
48.9 × 0.2072 .
3.94
Answer .......................................... [2]
2
5 By writing each number correct to one significant figure, estimate the value of
0.387 × 7.032 .
3
8.11
Answer ............................................ [2]
6 (a) Express, correct to two significant figures,
(i) 15 823.769,
Answer (a)(i) .................................. [1]
(ii) 0.003 048 9.
Answer (a)(ii) ................................. [1]
(b) Use your answers to part (a) to estimate, correct to one significant figure, the value of
15 823.769 × 0.003 048 9.
Answer (b) ...................................... [2]
3
7 (a) By writing each number correct to one significant figure, estimate the value of
7.84 × 326 .
0.18
Answer ........................................ [2]
(b) An athlete ran a race in 9.58 seconds, correct to the nearest hundredth of a second.
What is the shortest possible time that the athlete could have run the race?
Answer ..........................seconds [1]
8 (a) Express 0.047 852 correct to two decimal places.
Answer ........................................ [1]
(b) Estimate the value of 200 , giving your answer correct to two significant figures.
Answer ........................................ [1]
(c) By writing each number correct to one significant figure, estimate the value of
212 × 1.972 .
0.763
Answer ........................................ [2]
4
304.3 × √⎯1⎯5.⎯ ⎯9⎯8
9 By making suitable approximations, estimate the value of .
0.1975
Answer ....................................... [2]
10 By writing each number correct to two significant figures, estimate, correct to one significant figure,
the value of
110.94 – 0.2034 × 368.62 .
Answer ........................................ [2]
5
11 (a) Evaluate 6 × 3 + 8 ÷ 2 .
Answer ..................................... [1]
(b) By writing each number correct to 1 significant figure, estimate the value of
19.2 × 9.09 .
0.583
Answer ..................................... [2]
12 (a) Estimate, correct to the nearest whole number, the value of 72 .187 .
π
Show clearly the approximate values you use.
Answer ..................................... [1]
(b) The values of three cube roots, correct to 1 decimal place, are given below.
35 3 50 3 500
= 1.7 = 3.7 = 7.9
3
Using as much of the above information as is necessary, find the value of 0.005 .
Answer ..................................... [1]
6
13 (a) Write the number 0.040 589 correct to 3 significant figures.
Answer ..................................... [1]
(b) Giving your answer in standard form, evaluate 6 × 10–4 + 8 × 10–5.
Answer ..................................... [1]
(c) Estimate, correct to the nearest whole number, the value of 97 – 35 .
Show clearly the approximate values you use.
Answer ..................................... [1]
14 (a) Write 0�004 075 1 correct to two significant figures�
Answer �������������������������������������������� [1]
(b) 131 lies between two consecutive integers�
Complete the inequality below with these integers�
Answer ������������ 1 131 1 ������������� [1]
(c) Add brackets to the statement below to make it correct�
3 × 2 + 1 2 = 49 [1]
7
38.982 # 8.8536
15 By making suitable approximations, estimate the value of .
6.0122
Show clearly the approximate values you use.
Answer ................................................ [2]
3
35.78 # 1005
16 By making suitable approximations, estimate the value of .
0.3012
Show clearly the approximate values you use.
Answer ............................................... [2]
17 (a) By writing each number correct to one significant figure, estimate the value of
28.6 + 47.7
.
0.47 # 21.4
Answer .......................................................... [2]
8
(b) Write as a decimal.
25
Answer .......................................................... [1]
8
18 (a) Write 405 917 628 correct to three significant figures.
Answer .............................................................. [1]
(b) By writing each number correct to one significant figure, estimate the value of
41.3
.
9.79 # 0.765
Answer .............................................................. [2]
19 (a) Write the number forty one thousand and six in figures.
Answer ......................................... [1]
(b) Write 237 400 correct to two significant figures.
Answer ......................................... [1]
20 (a) Write the value of 1234.567, correct to 2 significant figures.
Answer ............................................. [1]
28
(b) Write down an estimate for the value of .
r
Answer ............................................. [1]
9
(a) Correct to 6 decimal places, 10 = 3.162 278, 3
1
21 = 3.166 667.
6
Find the difference between 3
1
and 10.
6
Give your answer correct to 2 significant figures.
Answer .............................................. [1]
(b) Estimate, correct to the nearest whole number, the value of 2.986 2 + 4.002 2 .
Answer .............................................. [1]
22 Bywritingeachnumbercorrecttoonesignificantfigure,estimatethevalueof
29.3 2 .
2.04 # 0.874
Answer��������������������������������������������� [2]
23 (a) Write 30 682 correct to three significant figures.
Answer ........................................ [1]
(b) Given that 538 × 210 = 112 980, evaluate 112.98 ÷ 210.
Answer ........................................ [1]
10
24 (a) Write the number 0.050 462 correct to 3 significant figures.
Answer ................................................. [1]
(b) By writing each number correct to 1 significant figure, estimate the value of
8.94 # 0.201
.
28.8
Answer ................................................. [1]
25 By writing each number correct to 1 significant figure, estimate the value of
29.2 # 8.17 .
0.396
Answer ............................................. [2]
26 (a) Write the number 357.864 correct to 2 significant figures.
Answer .......................................... [1]
3
67
(b) Estimate, correct to the nearest whole number, the value of .
1.03
Answer .......................................... [1]
11
3.98 # 602.3
27 By making suitable approximations, estimate the value of .
2.987
Show clearly the approximations you use.
Answer .......................................... [2]
28 (a) Write 248.367
(i) correct to 2 decimal places,
Answer ........................................... [1]
(ii) correct to 2 significant figures.
Answer ........................................... [1]
3 3
(b) Estimate, correct to the nearest whole number, the value of 8.36 + 63.58 .
Answer ........................................... [1]
12
29 By writing each number correct to one significant figure, estimate the value of
58.7 # 4.08
.
19.7 3
Answer ........................................... [2]
