Integers, Fractions and Decimals
7 questions, 24 marks, every one with its mark scheme.
Or open them one at a time, as you finish each question.
Question 1
3 marksShow that 334 ÷ 217 = 134
You must write down all the stages in your working.
Mark scheme
- Both mixed numbers as improper fractions: 154 and 157M1
- Multiplies by the reciprocal: 154 × 715M1
- 10560 = 74 = 134 from correct workingA1*
Do not accept: working in decimals
Question 2
5 marksWrite 4116 as a product of powers of its prime factors.
Show your working clearly.
Mark scheme
- At least two correct stages of splitting 4116 into factors (factor tree or ladder)M1
- All the prime factors 2, 2, 3, 7, 7, 7 foundM1
- 22 × 3 × 73A1
Do not accept: 22, 3, 73 (a list); 22 + 3 + 73; 4 × 3 × 343 (composite factors)
Hence write 4116 × 104 as a product of powers of its prime factors.
Mark scheme
- 104 = 24 × 54M1
- 26 × 3 × 54 × 73A1ft
Do not accept: 22 × 3 × 73 × 104 (10 is not prime)
Question 3
2 marksFind the lowest common multiple (LCM) of 96 and 180.
Show your working clearly.
Mark scheme
- 96 = 25 × 3 and 180 = 22 × 32 × 5, or lists of at least four multiples of eachM1
- 1440A1
Do not accept: 12 (the HCF)
Question 4
3 marksShow that 416 − 234 = 1512
You must write down all the stages in your working.
Mark scheme
- Both mixed numbers as improper fractions: 256 and 114M1
- Both over a common denominator of 12: 5012 − 3312M1
- 1712 = 1512 from correct workingA1*
Do not accept: working in decimals
Question 5
2 marksUse algebra to show that 0.218 = 1255
Mark scheme
- x = 0.21818…, 1000x = 218.1818… and 10x = 2.1818… with 1000x − 10x = 216M1
- 990x = 216, x = 216990 = 1255A1*
Do not accept: a decimal check with no equations in x
Question 6
2 marksUse algebra to show that 1.207 = 123111
Mark scheme
- x = 1.207207… and 1000x = 1207.207207… with 1000x − x = 1206M1
- 999x = 1206, x = 1206999 = 134111 = 123111A1*
Do not accept: a decimal check with no equations in x
Question 7
7 marksA = 23 × 3 × 52
B = 2 × 34 × 7
Find the highest common factor (HCF) of 6A and 5B.
Give your answer as a product of powers of its prime factors.
Mark scheme
- 6A = 24 × 32 × 52 or 5B = 2 × 34 × 5 × 7M1
- 2 × 32 × 5A1
Do not accept: 2 × 3 (the HCF of A and B)
Find the lowest common multiple (LCM) of 6A and 5B.
Give your answer as a product of powers of its prime factors.
Mark scheme
- Takes the higher power of every prime in 6A and 5BM1
- 24 × 34 × 52 × 7A1
Work out the value of A2 × B.
Give your answer as a product of powers of its prime factors.
Mark scheme
- A2 = 26 × 32 × 54M1
- 27 × 36 × 54 × 7A1
C = 2p × 32 × 5
The HCF of A and C is 22 × 3 × 5
Write down the value of p.
Mark scheme
- p = 2B1