Math review

Find each of the following by using prime factorisation

• 42

• 63

• 51

• 78

Determine whether each of the following is a prime number or a composite 87

• Composite

• Prime

Given that the prime factorisation 9801 is 3 4times 11 2times 9801 without using a calculator

• 99

• 87

• 63

• 937

Given that the prime factorisation 21 952 is 2 6times 7 3times 21 952 without using a calculator

• 92

• 37

• 54

• 28

Estimate the value of 66

• 7

• 5

• 8

• 6

Find the highest common factor of 12 and 30

• 5

• 6

• 4

• 9

Find the lowest common multiple of 42 and 462

• 456

• 986

• 462

• 567

Find the largest whole number which is a factor of both 42 and 98

• 14

• 65

• 92

• 35

The numbers 792 and 990 written as the product of their prime factors are 792 2 3times×3 2times×11 and 990 2×3 2times×5×11 Hence find the greatest whole number that will divide both 792 and 990 exactly

• 786

• 654

• 244

• 198

The numbers 176 and 342 written as the product of their prime factors are 176 2 4times×11 and 342 2 3times×

3 2times×19 Hence find the greatest whole number that will divide both 176 and 342 exactly

• 786

• 30 096

• 244

• 198