Name ………………………………………………………….

ADM Number……………
Candidate’s signature……………………Class…………
121/1
MATHEMATICS
Paper 1
MARCH, 2024
Time 2½ Hours

BIG SIX JOINT EXAMINATION

Kenya Certificate of Secondary Education
121/1
MATHEMATICS
Paper 1
MARCH, 2024
2½ Hours
Instructions to candidates
a) Write your name and index number in the spaces provided above.
b) Sign and write the date of examination in the spaces provided above.
c) This paper consists of two sections: Section I and Section II.
d) Answer all the questions in Section I and only five questions from Section II.
e) Show all the steps in your calculations, giving your answers at each stage in the spaces
provided below each question.
f) Marks may be given for correct working even if the answer is wrong.
g) Non-programmable silent electronic calculator and KNEC mathematical tables may be
used, except where stated otherwise.
h) Candidates should check the question paper to ascertain that all the pages are printed as
indicated and that no questions are missing.
i) Candidates should answer the questions in English.
For examiner’s use only
Section 1
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Total

Section II

17 18 19 20 21 22 23 24 Total

Page 1 of 17
 SECTION I (50 marks)
Answer all the questions in section I
3
1. Evaluate /4 + 15/7 ÷ 4/7 of 21/3 (3 marks)
(13/7 – 5/8) x 2/3

2. Simplify 8x2 + 6x – 9 (3 marks)

16x2 – 9

3. Two similar solid cones made of the same material have masses of 8000g and 1000g
respectively. If the base area of the smaller cone is 77cm2, calculate;
a) The base area of the larger cone (2 marks)

b) The radius of the larger cone (2 marks)

Page 2 of 17
4. Given that cos(2x)° - sin(4x+30)° = 0. Calculate the value of x (3 marks)

5. A line L passes through point (3,1) and is perpendicular to the line 2y=4x+5. Determine the
equation of the line L. (3 marks)

6. A Kenyan tourist left Germany for Kenya through Switzerland. While in Switzerland, he
bought a watch worth 52 Deutsche marks. Using the exchange rates below.
1 Swiss Franc = 1.28 Deutsche Marks
1 Swiss Franc = 45.21 Kenya shillings
Find the value of the watch to the nearest (2 marks)
(i) Swiss Franc

(ii) Kenya shillings (2 marks)

Page 3 of 17
7. State all integral values of x which satisfy the following pair of inequalities. (3 marks)
1
3  x  1 x
2
1
 x  5  7  x
2

8. A man is now three times as old as his daughter. In twelve years time he will be twice as old
as his daughter. Find their present ages. (3 marks)

9. The point A(3, 2) is mapped onto A1(7, 1) under a translation T. Find the co-ordinates of the
image of B(4, 6) under the same translation. (3 marks)

Page 4 of 17
10. Calculate the area of the trapezium below. (3 marks)
7cm

4√3 h

60°

11cm

11. (4 marks)

12. (3 marks)

Page 5 of 17
13. A square brass plate is 2mm thick and has a mass of 1.05kg. The density of the brass plate is
8.4g/cm3. Calculate the length of the plate in cm. (3 marks)

14. The sum of interior angles of two regular polygons of side n-1 and n are in the ratio 4:5.
Calculate;
(i) the value of interior angle of the polygon with side (n-1) (2 marks)

(ii) exterior angle (1 mark)

15. Four athletes Onyango, Korir, Njuguna and Mutua can complete a 2km lap in a field in 12
minutes, 15 minutes, 18 minutes and 20 minutes respectively. If they start the race together,
find the number of times the slowest athlete will be overlapped by the fastest athlete by the
time they next cross the finish line simultaneously. (3 marks)

Page 6 of 17
16. The figure below shows a triangular prism. Given that AB= 3cm,AC=4cm, CB=5cm and
BD=6 cm. Draw its net. (3 marks)
E

D
F
C

B
A

Page 7 of 17
 Section II (50 marks)

Answer only five questions from this section in the spaces provided.

Page 8 of 17
18. Four towns P, Q, R and S are such that Q is 160km from town P on a bearing of 065°. R is
280km on a bearing of 152° from Q. S is due west of R on a bearing of 155° from P. Using
a scale of 1cm to represent 40km.

a) Show the relative positions of P, Q, R and S. (4 marks)

b) Find the bearing of;

(i) S from Q (1 mark)

(ii) P from R (1 mark)

c) Find the distance in km

(i) PS (2 marks)

(ii) RS (2 marks)

Page 9 of 17
Page 10 of 17
20. A particle moves from rest and attains a velocity of 10m/s after two seconds it then moves
with 10m/s velocity for 4 seconds. It finally decelerates uniformly and comes to rest after 6
seconds.

a) Draw a velocity time graph for the motion of this particle (3 marks)

b) From the graph find;

(i) the acceleration during the first two seconds. (2 marks)

(ii) the uniform deceleration during the last six seconds. (2 marks)

(iii) the total distance covered by the particle (3 marks)

Page 11 of 17
21. A business lady bought 100 quails and 80 rabbits for sh25600. If she had bought twice as
many rabbits and half as many quails she would have paid sh7400 less. She sold each quail at
a profit of 10% and each rabbit at a profit of 20%.
a) Form two equations to show how much she bought the quails and the rabbits. (2marks)

b) Using matrix method, find the cost of each animal. (5mrks)

c) Calculate the total percentage profit she made from sale of the 100 quails and 80 rabbits.
(3 marks)

Page 12 of 17
Page 13 of 17
Page 14 of 17
23. A quadrilateral ABCD with vertices A(2, 6), B(4, 8), C(5, 6) and D(3, 4) is mapped onto
quadrilateral AIBICIDI by a reflection in the line y = -x+5.

a) On the grid provided draw the quadrilateral ABCD and its image A1B1C1D1 under
reflection in the line y= -x+5 (5 marks)

Page 15 of 17
b) Quadrilateral AIIBIICIIDII is the image of quadrilateral AIBICIDI under a negative
quarter turn about (1, -1). On the same grid, draw quadrilateral AIIBIICIIDII and state
the coordinates of the image (3 marks)

c) Quadrilateral AIIIBIIICIIIDIII is the image of quadrilateral AIIBIICIIDII under an

enlargement with scale factor -1 about (1,-1). On the same grid, draw AIIIBIIICIIIDIII
and state the co-ordinates of the image. (2 marks)

Page 16 of 17
Page 17 of 17