121/1
MATHEMATICS
Paper 1
Time: 2½hours
MATHEMATICS PAPER 1 MARKING
SCHEME
Kenya Certificate of Secondary Education
121/1
Paper 1
MATHEMATICS
1. 2 5 4+5 9 5 18−15 3 1 M1
=
= − = = =
3 6 6 6 21 12 4
4 1
7 11 77
16 9 160+27 187
16
=
+ = 3 10 30 30 5 × = M1 A1
3 15
2 77 30+539 569 513
187 −
19635 2565 =
- 6
3150
17070 630
+ = =
7 15 105 105 3150
30
1 630 −315
=
×
4 513 1026
2. 1 2
√ 6.458 × 10−2 2( ) M1
0.4327
2.541 + (2.311)2 M1
= 2.541 + 2(5.307) M1
= 2.541 + 10.61 A1
=13.155
, 3. log29 + log M1
M1
A1
4 M1 A1
= 7.007 units
5. 150
600 M1
3 3000
51 x 57000 x 100000
68 x 95 x 100
45
1 1
= 3 x 150 x 1000 M1
A1
= 450,000
2
6 x3 M1
x
3 1
( 2) ( 1) M1
A1
6
MATHEMATICS
Paper 1
Time: 2½hours
MATHEMATICS PAPER 1 MARKING
SCHEME
Kenya Certificate of Secondary Education
121/1
Paper 1
MATHEMATICS
1. 2 5 4+5 9 5 18−15 3 1 M1
=
= − = = =
3 6 6 6 21 12 4
4 1
7 11 77
16 9 160+27 187
16
=
+ = 3 10 30 30 5 × = M1 A1
3 15
2 77 30+539 569 513
187 −
19635 2565 =
- 6
3150
17070 630
+ = =
7 15 105 105 3150
30
1 630 −315
=
×
4 513 1026
2. 1 2
√ 6.458 × 10−2 2( ) M1
0.4327
2.541 + (2.311)2 M1
= 2.541 + 2(5.307) M1
= 2.541 + 10.61 A1
=13.155
, 3. log29 + log M1
M1
A1
4 M1 A1
= 7.007 units
5. 150
600 M1
3 3000
51 x 57000 x 100000
68 x 95 x 100
45
1 1
= 3 x 150 x 1000 M1
A1
= 450,000
2
6 x3 M1
x
3 1
( 2) ( 1) M1
A1
6
