Guidance
Notes
AO Element
Marks
Answer
Question
B1 for 14x or 13y as
answers
2
final answer
1
If 0 scored, SC1 for
correct answer seen then
spoilt
1
Diagram 4 correctly drawn
2(a)
1
28
2(b)
M1 for
or
2
8n − 4 oe final answer
2(c)
M1 for
their (a)(iii) = 300
provided their (a)(iii) is
linear
2
38
2(d)
M1 for 7 × 7 × 14
or 0.07 × 0.07 × 0.14
or 70 × 70 × 140 oe
3
B2 for 686
2(e)
Units must be consistent
with working or
numerical answer
B1 for cm3
M1 for
oe
2
18a final answer
3(a)
M1 for
2
14a 2
final answer
3(b)
/
- Mark Scheme
Guidance
Notes
AO Element
Marks
Answer
Question
B1 for 2 correct
or 5 6 9
2
6 9 14
4
B2 for 4 or 5 correct
3
−4 −6 −12 6 4 3
5(a)
or B1 for 2 or 3 correct
B3FT for 9 or 10 points
correctly plotted
4
Correct curve
5(b)
or B2FT for 7 or 8 points
correctly plotted
or B1FT for 5 or 6 points
correctly plotted
1
Correct ruled line drawn
5(c)
FT their curve and their
line
1
1.3 to 1.7
5(d)
M1 for oe
or
2
or final answer
6
/
- Mark Scheme
Guidance
Notes
AO Element
Marks
Answer
Question
oe
3
M1 for correct method seen to
eliminate one variable
7
A1 for x = 4
If M0 scored, SC1 for 2
values that substitute to
give
y – 3x rounding to 13.0,
or
y – 7x rounding to
−3.0
A1 for y = 25
or
SC1 if no working
shown, but 2 correct
answers given
M1 for 90 ÷ their time
for A to B [× 60]
2
120
8(a)(i)
or B1 for 2[km/min]
1
10
8(a)(ii)
1
Ruled line from (1440, 90) to
(1520, 155)
8(a)(iii)
1
A [and] B
8(a)(iv)
M1 for 155 ÷ 62
2
2 [hours] 30 [minutes]
8(b)(i)
FT their (b)(i) + 1245
1
1515
8(b)(ii)
/
- Mark Scheme
Guidance
Notes
AO Element
Marks
Answer
Question
1
Ruled line from (1245, 155) to
(their (b)(ii), 0)
8(b)(iii)
FT their crossing
point
1
58 to 63
8(b)(iv)
B1 for 2 correct
2
−3 5 2
9(a)
B3FT for 6 or 7 points
correct
4
Correct curve
9(b)
or B2FT for 4 or 5 points
correct
or B1FT for 2 or 3 points
correct
1
Ruled line x = 1 drawn
9(c)(i)
1
x = 1
9(c)(ii)
B1 for each
2
−0.5 to −0.3 and 2.3 to 2.5
9(d)
If 0 scored, B1 for y = 4
drawn
1
Correct ruled continuous line
9(e)(i)
/
- Mark Scheme
Guidance
Notes
AO Element
Marks
Answer
Question
B2 for [y =] 2x + k
3
[y =] 2x + 4
9(e)(ii)
or M1 for
B1 for kx + 4 , k ≠ 0,
or c = 4
1
80
10(a)
M1 for or
or better
2
7
10(b)
M1 for
or
3
2.2 oe
10(c)
M1 for second correct
step
B1 for
or
2
final answer
11
M1 for 4 × 32
+ 3 × −2
or better
2
30
12
/
- Mark Scheme
Guidance
Notes
AO Element
Marks
Answer
Question
B3 for 14x = 315
4
22.5
13
or M2 for
45 + 3x + 5x + 6x = 360
oe
or M1 for
45 + 3x + 5x + 6x oe
or 14x
If 0 scored and
45 + bx = 360 or better
seen then
SC1 for
oe
OR
B3 for
or B1 for 14
and B1 for 360 − 45 oe
1
3
14(a)
B1 for 3 or 4 correct
2
_ _ _ 10
14(b)
_ 1 _ 6
_ _ 9 16
1
[t =] n 2
oe
14(c)
/
- Mark Scheme
Guidance
Notes
AO Element
Marks
Answer
Question
2
M1 for
or
14(d)
A1 for [=] 6
3
B1 for [w =] 120
14(e)
B1 for [g =] 105
If final two B marks not
scored, award B1 if
their w + their g = their t
or FT(c) for their t if
their (c) is quadratic
B1 for [t =] 225
1
y = −2 drawn, ruled
15(a)
1
y = −2x drawn, ruled
15(b)
M1 for a correct equation
in terms of x or y.
2
[x =] 3.5, [y =] 3
with supporting working
16
If 0 scored SC1 for both
answers correct.
1
cao
17(a)
1
cao
17(b)
/
- Mark Scheme
Guidance
Notes
AO Element
Marks
Answer
Question
M1 for ,
or or
or
2
18
as final
answers
1
4 tables and 14 chairs correctly
drawn
19(a)
B1 for 2 correct
or k, k + 2, k + 4
2
14, 16, 18
19(b)
B1 for 2t + j
or kt + 6 , k ≠ 0
2
2t + 6 oe final answer
19(c)
M1 for 18 correctly
substituted into their (c),
2
42 cao
19(d)
provided a linear
expression
M1 for their (c) = 80
2
37 cao
19(e)
1
55
20(a)
M1 for oe
2
108
20(b)
/
- Mark Scheme
Guidance
Notes
AO Element
Marks
Answer
Question
4
Correct graph
Ruled lines
20(c)
B1 for ruled lines
(0955, 31.5) to
(1030, 31.5)
and (1030, 31.5) to
(1050, 30)
(0955, 31.5) to (1030, 31.5)
(1030, 31.5) to (1050, 30)
B1 for ruled line from
(their 1050, 30) to
(their 1050+20, 12)
(1050, 30) to (1110, 12)
B1 for ruled line from
(their 1110, 12) to
(their 1110+10, 12)
(1110, 12) to (1120, 12)
B1 for ruled line
(their 1120, 12) to
(their 1120+15, 0)
or for 15 mins soi
(1120, 12) to (1135, 0)
B1 for each
3
–28, –4, 2
21(a)
B3FT for 6 or 7 correct
plots
4
correct smooth curve
21(b)
or B2FT for 4 or 5
correct plots
or B1FT for 2 or 3
correct plots
accept (x, y) where
1 < x < 2 and 2 < y < 4
1
(1.5 , 2.25)
21(c)
/
- Mark Scheme
Guidance
Notes
AO Element
Marks
Answer
Question
B1 for or
2
final answer
22
B1 for 25 or 12
2
37
23
1
cao
24
1
1025
25(a)
B1 for line from
(1055, 9) to (1120, 9)
2
Graph completed correctly
25(b)
B1 FT for line from
(their 1120, 9) to
(their 1120 + 30 min,
0)
B1 for 5x – 15 or 6x + 2
or for answer of 11x + j
or kx – 13
2
11x – 13 final answer
26
1
23
27(a)
B1 for 3n + j or kn + 5,
k ≠ 0
2
3n + 5 oe
27(b)
/
- Mark Scheme
Guidance
Notes
AO Element
Marks
Answer
Question
4
M1 for multiplying both equations
to get a common coefficient
28
M1 for correctly adding or
subtracting their equations
A1 for [x = ] 10
If zero scored then SC1
for two answers which
A1 for [y = ] 8
satisfy one of the original
equations or for 2 correct
answers with no
working
If zero scored, SC1 for 2
values satisfying one of
3
M1 for correctly eliminating one
variable
29
the original equations or
A1 for [x = ] 3
for 2 correct answers
with no working
A1 for [y = ] −2
1
45
30
B1 for 6n + c or kn – 10
(k ≠ 0)
2
6n – 10 oe
31
/
- Mark Scheme
Guidance
Notes
AO Element
Marks
Answer
Question
Examples
3
M1 for any example of equivalence
from the conversion graph
32
Pounds (£)
Dollars ($)
3.5
5
7
10
14
20
21
30
28
40
5
7
10
14 to 14.5
15
21
20
28 to 29
A1 for [£]81 to [£]87 or
[$]126 to [$]138
A2 for shop and [£]81 to [£]87
or [$]126 to [$]138 nfww
If M0 allow SC1 for
[$]120 = [£]81 to [£]87
or [£]90 = [$]126 to
[$]138 with ‘shop’ as the
answer
B1 for −3p or −4q
2
−3p – 4q final answer
33
M1 for or
or better
2
13
34
/
- Mark Scheme
Guidance
Notes
AO Element
Marks
Answer
Question
M1 for first correct
step
3
0.7 or
35
M1 for second correct
step, FT their first step
1
y(1 – 2y) final answer
36
M1 for 3x + x + x + 15 or
better
4
3x + x + x + 15 = 180 or better
leading to
[x = ] 33
37
M1 for their expression
= 180
M1 for rearranging their
equation to ax = b
If 0 scored, SC2 for 33
nfww
M1 for x – 3 = 8
or 7x – 21 = 56 or
better
2
11
38
M1 for or
2
oe
39
M1 for or
better
2
32
40
/
- Mark Scheme
Guidance
Notes
AO Element
Marks
Answer
Question
[Total: 154]
/
- Mark Scheme

ALGEBRA FOR IGCSE STUDENTS GOOD MARKING SCHEME

  • 1.
    Guidance Notes AO Element Marks Answer Question B1 for14x or 13y as answers 2 final answer 1 If 0 scored, SC1 for correct answer seen then spoilt 1 Diagram 4 correctly drawn 2(a) 1 28 2(b) M1 for or 2 8n − 4 oe final answer 2(c) M1 for their (a)(iii) = 300 provided their (a)(iii) is linear 2 38 2(d) M1 for 7 × 7 × 14 or 0.07 × 0.07 × 0.14 or 70 × 70 × 140 oe 3 B2 for 686 2(e) Units must be consistent with working or numerical answer B1 for cm3 M1 for oe 2 18a final answer 3(a) M1 for 2 14a 2 final answer 3(b) / - Mark Scheme
  • 2.
    Guidance Notes AO Element Marks Answer Question B1 for2 correct or 5 6 9 2 6 9 14 4 B2 for 4 or 5 correct 3 −4 −6 −12 6 4 3 5(a) or B1 for 2 or 3 correct B3FT for 9 or 10 points correctly plotted 4 Correct curve 5(b) or B2FT for 7 or 8 points correctly plotted or B1FT for 5 or 6 points correctly plotted 1 Correct ruled line drawn 5(c) FT their curve and their line 1 1.3 to 1.7 5(d) M1 for oe or 2 or final answer 6 / - Mark Scheme
  • 3.
    Guidance Notes AO Element Marks Answer Question oe 3 M1 forcorrect method seen to eliminate one variable 7 A1 for x = 4 If M0 scored, SC1 for 2 values that substitute to give y – 3x rounding to 13.0, or y – 7x rounding to −3.0 A1 for y = 25 or SC1 if no working shown, but 2 correct answers given M1 for 90 ÷ their time for A to B [× 60] 2 120 8(a)(i) or B1 for 2[km/min] 1 10 8(a)(ii) 1 Ruled line from (1440, 90) to (1520, 155) 8(a)(iii) 1 A [and] B 8(a)(iv) M1 for 155 ÷ 62 2 2 [hours] 30 [minutes] 8(b)(i) FT their (b)(i) + 1245 1 1515 8(b)(ii) / - Mark Scheme
  • 4.
    Guidance Notes AO Element Marks Answer Question 1 Ruled linefrom (1245, 155) to (their (b)(ii), 0) 8(b)(iii) FT their crossing point 1 58 to 63 8(b)(iv) B1 for 2 correct 2 −3 5 2 9(a) B3FT for 6 or 7 points correct 4 Correct curve 9(b) or B2FT for 4 or 5 points correct or B1FT for 2 or 3 points correct 1 Ruled line x = 1 drawn 9(c)(i) 1 x = 1 9(c)(ii) B1 for each 2 −0.5 to −0.3 and 2.3 to 2.5 9(d) If 0 scored, B1 for y = 4 drawn 1 Correct ruled continuous line 9(e)(i) / - Mark Scheme
  • 5.
    Guidance Notes AO Element Marks Answer Question B2 for[y =] 2x + k 3 [y =] 2x + 4 9(e)(ii) or M1 for B1 for kx + 4 , k ≠ 0, or c = 4 1 80 10(a) M1 for or or better 2 7 10(b) M1 for or 3 2.2 oe 10(c) M1 for second correct step B1 for or 2 final answer 11 M1 for 4 × 32 + 3 × −2 or better 2 30 12 / - Mark Scheme
  • 6.
    Guidance Notes AO Element Marks Answer Question B3 for14x = 315 4 22.5 13 or M2 for 45 + 3x + 5x + 6x = 360 oe or M1 for 45 + 3x + 5x + 6x oe or 14x If 0 scored and 45 + bx = 360 or better seen then SC1 for oe OR B3 for or B1 for 14 and B1 for 360 − 45 oe 1 3 14(a) B1 for 3 or 4 correct 2 _ _ _ 10 14(b) _ 1 _ 6 _ _ 9 16 1 [t =] n 2 oe 14(c) / - Mark Scheme
  • 7.
    Guidance Notes AO Element Marks Answer Question 2 M1 for or 14(d) A1for [=] 6 3 B1 for [w =] 120 14(e) B1 for [g =] 105 If final two B marks not scored, award B1 if their w + their g = their t or FT(c) for their t if their (c) is quadratic B1 for [t =] 225 1 y = −2 drawn, ruled 15(a) 1 y = −2x drawn, ruled 15(b) M1 for a correct equation in terms of x or y. 2 [x =] 3.5, [y =] 3 with supporting working 16 If 0 scored SC1 for both answers correct. 1 cao 17(a) 1 cao 17(b) / - Mark Scheme
  • 8.
    Guidance Notes AO Element Marks Answer Question M1 for, or or or 2 18 as final answers 1 4 tables and 14 chairs correctly drawn 19(a) B1 for 2 correct or k, k + 2, k + 4 2 14, 16, 18 19(b) B1 for 2t + j or kt + 6 , k ≠ 0 2 2t + 6 oe final answer 19(c) M1 for 18 correctly substituted into their (c), 2 42 cao 19(d) provided a linear expression M1 for their (c) = 80 2 37 cao 19(e) 1 55 20(a) M1 for oe 2 108 20(b) / - Mark Scheme
  • 9.
    Guidance Notes AO Element Marks Answer Question 4 Correct graph Ruledlines 20(c) B1 for ruled lines (0955, 31.5) to (1030, 31.5) and (1030, 31.5) to (1050, 30) (0955, 31.5) to (1030, 31.5) (1030, 31.5) to (1050, 30) B1 for ruled line from (their 1050, 30) to (their 1050+20, 12) (1050, 30) to (1110, 12) B1 for ruled line from (their 1110, 12) to (their 1110+10, 12) (1110, 12) to (1120, 12) B1 for ruled line (their 1120, 12) to (their 1120+15, 0) or for 15 mins soi (1120, 12) to (1135, 0) B1 for each 3 –28, –4, 2 21(a) B3FT for 6 or 7 correct plots 4 correct smooth curve 21(b) or B2FT for 4 or 5 correct plots or B1FT for 2 or 3 correct plots accept (x, y) where 1 < x < 2 and 2 < y < 4 1 (1.5 , 2.25) 21(c) / - Mark Scheme
  • 10.
    Guidance Notes AO Element Marks Answer Question B1 foror 2 final answer 22 B1 for 25 or 12 2 37 23 1 cao 24 1 1025 25(a) B1 for line from (1055, 9) to (1120, 9) 2 Graph completed correctly 25(b) B1 FT for line from (their 1120, 9) to (their 1120 + 30 min, 0) B1 for 5x – 15 or 6x + 2 or for answer of 11x + j or kx – 13 2 11x – 13 final answer 26 1 23 27(a) B1 for 3n + j or kn + 5, k ≠ 0 2 3n + 5 oe 27(b) / - Mark Scheme
  • 11.
    Guidance Notes AO Element Marks Answer Question 4 M1 formultiplying both equations to get a common coefficient 28 M1 for correctly adding or subtracting their equations A1 for [x = ] 10 If zero scored then SC1 for two answers which A1 for [y = ] 8 satisfy one of the original equations or for 2 correct answers with no working If zero scored, SC1 for 2 values satisfying one of 3 M1 for correctly eliminating one variable 29 the original equations or A1 for [x = ] 3 for 2 correct answers with no working A1 for [y = ] −2 1 45 30 B1 for 6n + c or kn – 10 (k ≠ 0) 2 6n – 10 oe 31 / - Mark Scheme
  • 12.
    Guidance Notes AO Element Marks Answer Question Examples 3 M1 forany example of equivalence from the conversion graph 32 Pounds (£) Dollars ($) 3.5 5 7 10 14 20 21 30 28 40 5 7 10 14 to 14.5 15 21 20 28 to 29 A1 for [£]81 to [£]87 or [$]126 to [$]138 A2 for shop and [£]81 to [£]87 or [$]126 to [$]138 nfww If M0 allow SC1 for [$]120 = [£]81 to [£]87 or [£]90 = [$]126 to [$]138 with ‘shop’ as the answer B1 for −3p or −4q 2 −3p – 4q final answer 33 M1 for or or better 2 13 34 / - Mark Scheme
  • 13.
    Guidance Notes AO Element Marks Answer Question M1 forfirst correct step 3 0.7 or 35 M1 for second correct step, FT their first step 1 y(1 – 2y) final answer 36 M1 for 3x + x + x + 15 or better 4 3x + x + x + 15 = 180 or better leading to [x = ] 33 37 M1 for their expression = 180 M1 for rearranging their equation to ax = b If 0 scored, SC2 for 33 nfww M1 for x – 3 = 8 or 7x – 21 = 56 or better 2 11 38 M1 for or 2 oe 39 M1 for or better 2 32 40 / - Mark Scheme
  • 14.