# Module 1 - Unit 4: Extending Number Work

## Self-Audit

For the multiple choice questions below, choose one answer, (a), (b), (c) or (d), that is CORRECT by clicking the appropriate box.
Calculators are NOT allowed unless it is indicated in the question.

## Section 4.1 - Addition and Subtraction of Negative Numbers

Question 1
 What is -4 + 5? (A) -9  (B) -1 (C) 1 (D) 9
Question 2
 What is the value of 5 – (-3)? (A) -8   (B) -2 (C) 2 (D) 8
Question 3
 What is the value of -3 – (-6)? (A) -9   (B) -3 (C) 3 (D) 9
Question 4
 Overnight, the temperature dropped from 11°C to -2°C. By how many degrees did the temperature fall? (A) -11°C   (B) -9°C (C) 9°C (D) 13°C

## Section 4.2 - Multiplication and Division of Negative Numbers

Question 5
 What is the value of 4 × (-7)? (A) -28   (B) -11 (C) 11 (D) 28
Question 6
 What is the value of (-7) × (-9)? (A) -63   (B) -16 (C) 16 (D) 63
Question 7
 What is the value of (-100) ÷ (-5)? (A) -20   (B) 0.05 (C) 20 (D) 500
Question 8
 What is the value of ( 8 × (-4) ) ÷ ( (-2) × (-2) ) ?
(A)-8   (B)-4
(C)4
(D)8

## Section 4.3 - Rounding

Question 9
 What is 3489, to the nearest 1000? (A) 3000   (B) 3400 (C) 3500 (D) 4000
Question 10
 What is 7.947, correct to 1 decimal place? (A) 7.9   (B) 7.94 (C) 7.95 (D) 8.0
Question 11
 What is 7.947, correct to 2 significant figures? (A) 7.9   (B) 7.94 (C) 7.95 (D) 8.0
Question 12
 What is 0.04759, correct to 2 significant figures? (A) 0.04   (B) 0.047 (C) 0.048 (D) 0.05

## Section 4.4 - Estimating

Question 13
 Which of the following values is a good estimate for the calculation below? 7.49 × 20.15 (A) 15   (B) 150 (C) 160 (D) 1500 Question 14
 By estimating, determine which of these calculations is NOT correct. (A) (7.31 + 6.29) ÷ (2.71 + 1.65) = 3.12 to 2 d.p.  (B) 49.47 ÷ (33.8 – 15.4) = 2.69 to 2 d.p. (C) (27.5 – 5.67 + 4.5) × 27.3 = 720 to 2 s.f. (D) (105.67 + 72.6) ÷ 4.7 = 3.8 to 1 d.p.
Question 15
Which of the following values is a good estimate for the calculation below?
 27.4 × 88.3 11.1
(A)2.4   (B)24
(C)240
(D)2400
Question 16
 Tickets for a football match cost \$9 each. If 4163 people go to the match, which of the following is a good estimate for the total amount of ticket money collected? (A) \$4000   (B) \$30000 (C) \$40000 (D) \$400000

## Section 4.5 - Calculator Logic - Brackets and Memory Keys

For the questions in this section you may use a calculator

Question 17
Calculate, correct to 1 d.p.
 7.3 + 4.5 8.2 – 5.9
(A)-4.5   (B)1.9
(C)5.1
(D)9.3
Question 18
Calculate
 7.57 + 3.21 9.61 ÷ 3.78
Give your answer correct to 1 d.p.
(A)0.3   (B)4.2
(C)7.7
(D)15.7
Question 19
 When David tried to calculate 4 on his 2 + 3 × 2
calculator, his answer was 0.4, which is wrong. What is the correct answer?
(A)0.5   (B)2
(C)5
(D)10
Question 20
Calculate, correct to 1 decimal place,
 5.2 × (6.21 + 13.07) (8.78 – 1.75) × 2.34
(A)1.1   (B)6.1
(C)15.1
(D)33.4 Mark your answers.