Number

23.
(a) Express 72 as a product of its prime factors.
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(b) Find the smallest positive integer value n for which 72n is a cube number.
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Paper 1
24.
Consider the given numbers:
0.4, 23, 23, 1, 2
Write down a number that is:
(a) Prime
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(b) Irrational
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(c) A square number
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Paper 1
25.
(a)(i) Express 130 as a product of its prime factors.
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(a)(ii) Find the smallest positive integer value n for which 130n is a multiple of 35.
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(b) Find the highest common factor (HCF) of 48 and 84.
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Paper 1
26.
24=2×2×2×3
(a) Find the smallest integer value of t for which 24 t 3 is an integer.
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(b) The number 240 can be expressed as a product of a cube number, j which is greater than 1, a composite number, k and a multiple of 5, l. Find the values of j, k and l.
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Paper 1
27.
(a) Write 520 as a product of its prime factors.
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(b) It is given that 1260=22×32×5×7. Find the highest common factor of 1260 and 520.
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Paper 1
28.
Consider the numbers:
π11, 8.215, 2337, 9, 643
Write the number which is:
(a) irrational
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(b) prime
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(c) a perfect square
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Paper 1
29.
From the list of numbers: 2.4, 5, 8%, 15, 16
Write:
(a) A composite number
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(b) An integer
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(c) An irrational number
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Paper 1
30.
From the following list of numbers:
3 π 2 32 35 121
Write:
(a) a multiple of 7
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(b) a factor of 8
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(c) a prime number
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(d) a square number
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(e) an irrational number
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Paper 1
31.
(a) Express 56 as the product of its prime factors.
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(b) The number P expressed as the product of its prime factors is 2×3×7. Find the HCF of 56 and P.
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Paper 1
7.
(a) Write 126 as a product of its prime factors.
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(b) Find the difference between the fifth prime number and the fourth composite number.
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(c) Show that 2.12 is rational.
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Paper 3
8.
In 1950, the population of Switzerland was 4 714 900. In 2000, the population was 7 087 000.

(a) Work out the percentage increase in the population from 1950 to 2000.
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(b) (i) Write the 1950 population correct to 3 significant figures.
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(ii) Write the 2000 population in standard form.
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Paper 3
9.
Write the numbers 0.5 2 , 0.5 , 0.5 3 in order with smallest first.
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Paper 3
10.
Work out 5 6 ( 1 2 × 1 1 2 ) .
Write down all the steps of your working.
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Paper 3
11.
Calculate 5 2 2 5 .
(a) Giving your answer as a fraction,
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(b) Giving your answer as a decimal.
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Paper 3
12.
Write down the next two prime numbers after 47.
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Paper 3
13.
Write 2 8 × 8 2 × 4 2 in the form 2 n .
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Paper 3
14.
Show that 1 5 9 ÷ 1 7 9 = 7 8 .
Write down all the steps in your working.
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Paper 3
15.
For this question, 1 < x < 2.
Write the following in order of size, smallest first.
5 x , 5 x , x 5 , x 5
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Paper 3
16.
1 1 2 + 1 3 + 1 4 = p 12 .
Work out the value of p. Show all your working.
p = ......................... [2]
Paper 3
17.
Without using a calculator, work out 6 7 ÷ 1 2 2 .
Write down all the steps in your working.
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Paper 3