0580/32 October/November 2021 Question 2: Prime Factorization

Question 1

Select from the list a number that 24 divides into exactly.

Accepted Answer

72 = 3 × 24, so 72 Answer: 72

Question 2

Select from the list a number that is the result of squaring an integer.

Accepted Answer

49 = 7², so 49 Answer: 49

Question 3

Select from the list a number that is the result of cubing an integer.

Accepted Answer

8 = 2³, so 8 Answer: 8

Question 4

Select from the list a number with exactly two factors.

Accepted Answer

17 has only factors 1 and 17, so 17 Answer: 17

Question 5

Express 420 as a multiplication of its prime factors.

Accepted Answer

420 = 2 × 210 = 2 × 2 × 105 = 2 × 2 × 3 × 35 = 2 × 2 × 3 × 5 × 7 420 = 2² × 3 × 5 × 7 Answer: 2² × 3 × 5 × 7

Question 6

Determine the smallest number that both 30 and 84 divide into exactly.

Accepted Answer

30 = 2 × 3 × 5 and 84 = 2² × 3 × 7 LCM = 2² × 3 × 5 × 7 = 420 Answer: 420

Question 7

Round each number in the expression to 1 significant figure and show the result is approximately 40.

Accepted Answer

9.875 ≈ 10, 18.305 ≈ 20, 3.418 ≈ 3, 27.837 ≈ 30 (10 + 20)/3 + 30 = 30/3 + 30 = 10 + 30 = 40 Answer: (10 + 20)/3 + 30 = 30/3 + 30 = 40

0580/32 Oct/Nov 2021, Question 2: Prime Factorization