Mr. B's Weebly - Grade 8 Mathematics



Extra Practice 1

|Lesson 3.1: What Is a Rational Number? |

|1. Which of the following numbers are equal to [pic]? |

|[pic] ____________________________________________ |

|2. Write the rational number represented by each letter as a decimal. |

|[pic] |

| |

|______________________________________________________________________ |

| |

|3. Write the rational number represented by each letter as a fraction. |

|[pic] |

| |

|______________________________________________________________________ |

| |

|4. Sketch a number line and mark each rational number on it. |

|Order the numbers from greatest to least. |

|–2.25, [pic], –1.5, [pic], 0.9 |

|5. In each pair, which rational number is greater? Explain how you know. |

|a) [pic] b) [pic] |

|c) [pic] d) [pic] |

|6. Diver A is 2.3 m below sea level. |

|Diver B is 1.7 m below sea level. |

|Diver C is 3.2 m below sea level. |

|a) Draw a vertical number line to show the location of the divers. |

|b) Which diver is farthest from the surface? Explain your thinking. |

Extra Practice 1

Lesson 3.1

1. [pic]

2. A: –1.8, B: –0.1, C: 0.6, D: –0.9

3. A: –1[pic], B: [pic], C: [pic]

4.

[pic], 0.9, [pic], –1.5, –2.25

5. a) –7.2 is greater because it is to the right

of –7.3 on a number line.

b) [pic] is greater because it is greater than 1 whereas [pic]is less than 1.

c) 1.2 is greater since it is positive.

d) One-eleventh is greater than one-thirteenth. So,[pic] is closer to 0 than [pic] on a number line. Since both numbers are negative, the number closer to 0, or farther to the right, is greater. So, [pic] is greater.

6. a)

b) Diver C because she is farthest from 0 on the number line

Extra Practice 2

|Lesson 3.2: Adding Rational Numbers |

|1. Write the addition statement that each number line represents. |

| |

| |

|a) |

| |

| |

| |

|b) |

|2. Determine each sum. |

|a) [pic] b) [pic] |

|c) [pic] d) [pic] |

|3. Sarah borrowed $40.25 from her parents for a new sweater. She earns $17.50 for a night of baby-sitting and gives this to her parents. |

|a) Write an addition statement to represent this situation. _________________________ |

| |

|b) How much does Sarah now owe? __________________________________________ |

| |

|4. Determine each sum. |

|a) [pic] b) [pic] |

| |

|5. Use integers to estimate each sum. Then, determine each sum. |

|a) [pic] b) [pic] |

|c) [pic] d) [pic] |

Extra Practice 2

Lesson 3.2

1. a) [pic] 1[pic]1[pic]

b) [pic]

2. a) [pic]

b) [pic]

c) [pic]

d) [pic]

3. a) –40.25 + 17.50 = –22.75

b) Sarah now owes $22.75.

4. a) [pic]

[pic]

b) [pic]

[pic]

5. Estimates may vary.

a) –25.5

b) 1.59

c) –3.55

d) –7.38

Extra Practice 3

|Lesson 3.3: Subtracting Rational Numbers |

|1. Write the subtraction statement that each number line represents. |

|a) |

|[pic] |

|b) |

|[pic] |

|2. Determine each difference. Describe the strategies you used. |

|a) [pic] b) [pic] |

| |

|3. Two climbers leave base camp at the same time. Climber A ascends 20.4 m, while climber B descends 35.4 m. How far apart are the climbers? |

|Write a subtraction statement using rational numbers to solve the problem. |

| |

|4. Predict whether each difference is positive or negative. Determine each difference. |

|a) 3[pic]4[pic] b) [pic] |

|5. Use integers to estimate each difference. Then, determine each difference. |

|a) [pic] |

| |

|b) [pic] |

| |

|c) [pic] |

|6. Determine the missing rational number in each addition statement. |

|a) [pic]3[pic] b) [pic]–2[pic] |

Extra Practice 3

Lesson 3.3

1. a) 1[pic]

b) –1[pic]–2[pic]

2. a) I sketched a number line.

[pic]

[pic]

b) I used common denominators.

[pic]

[pic]

3. 20.4 – (–35.4) = 55.8; the distance between the climbers is 55.8 m.

4. a) Negative

[pic]

[pic]

b) Positive

[pic]

5. a) Estimate: –11; Calculate: –10.6

b) Estimate: 0; Calculate: –0.41

c) Estimate: –35; Calculate: –34.47

6. a) [pic]

b) [pic]

Extra Practice 4

|Lesson 3.4: Multiplying Rational Numbers |

|1. Predict the sign of each product. Determine each product. |

|a) [pic] b) [pic] |

| |

| |

|c) [pic] d) [pic] |

| |

| |

|2. Predict the sign of each product. Determine each product. |

|a) [pic] |

| |

|b) [pic] |

| |

|c) [pic] |

| |

|3. From November 12th to November 21st, the temperature in Burnaby, B.C. dropped an average of 1.7°C each day. Suppose the temperature on the |

|morning of November 12th was 11.4°C. What was the temperature on the morning of November 21st? |

| |

| |

| |

| |

| |

|4. Use integers to estimate each product then calculate each product. |

|a) [pic] b) [pic] |

| |

| |

|5. Determine each product. |

|a) [pic] b) [pic] |

| |

Extra Practice 4

Lesson 3.4

1. a) Negative

(–1.2) × 0.3 = –0.36

b) Negative

0.34 × (–0.5) = –0.17

c) Positive

(–0.6) × (–0.15) = 0.09

d) Negative

0.9 × (–1.2) = –1.08

2. a) Negative

[pic]

b) Negative

[pic]

c) Positive

[pic]

3. [pic]

It was –3.9°C on the morning of Nov. 21.

4. a) Estimate: (1)(–13) = –13

Calculate: (1.19)(–13.2) = –15.708

b) Estimate: (–9)(–2) = 18

Calculate: (–8.65)(–1.6) = 13.84

5. a) [pic]

b) [pic]

Extra Practice 5

|Lesson 3.5: Dividing Rational Numbers |

|1. Determine each quotient. |

|a) i) [pic] ii) [pic] |

| |

| |

|b) i) [pic] ii) [pic] |

| |

|2. Predict the sign of each quotient, then calculate each quotient. |

|a) [pic] b) [pic] |

| |

| |

|c) [pic] d) [pic] |

| |

| |

|3. A diver descends 3.2 m in 5 min. What was his average rate of descent in metres per minute? |

| |

|4. Use a calculator to determine each quotient. Round each answer to the nearest hundredth. |

|a) [pic] b) [pic] |

| |

|5. Determine each quotient. |

|a) [pic] b) [pic] |

| |

| |

| |

|6. Replace each [pic] with a rational number to make each equation true. |

|a) [pic] b) [pic] |

| |

Extra Practice 5

Lesson 3.5

1. a) i) 8

ii) –8

b) i) 20

ii) 0.2

2. a) Negative

[pic]

b) Negative

[pic]

c) Positive

[pic]

d) Negative

[pic]

3. [pic]; So, the average rate of descent is 0.64 m/min.

4. a) 16.4 ÷ (–5.5) [pic] –2.98

b) (–0.98) ÷ 12.4 [pic] –0.08

5. a) [pic]

[pic]

b) [pic]

[pic]

6. a) (–0.64) ( 2.5 = –1.6

b) [pic]

Extra Practice 6

|Lesson 3.6: Order of Operations with Rational Numbers |

|1. Evaluate. Do not use a calculator. |

|a) [pic] b) [pic] |

| |

| |

|2. Evaluate. Do not use a calculator. |

|a) [pic] b) [pic] |

| |

| |

|3. A formula for the area of a trapezoid is [pic]where b and c are the lengths of the parallel sides and a is the perpendicular distance |

|between these sides. Use the formula to determine the area of a trapezoid with: [pic]cm, [pic]cm, [pic]cm. |

| |

| |

| |

|4. Evaluate. |

|a) [pic] b) [pic] |

| |

| |

| |

| |

| |

| |

| |

| |

|5. Evaluate this expression. Round the answer to the nearest hundredth. |

|[pic] |

| |

| |

| |

Extra Practice 6

Lesson 3.6

1. a) 4.5 + 5.1 ÷ 1.7 = 4.5 + 3 = 7.5

b) –5.8 – 3.1 × 0.5 = –5.8 – 1.55 = –7.35

2. a) [pic]

b) [pic]

[pic]

[pic]

[pic]

[pic]

[pic]

[pic]

3. Substitute.

A = [pic]

The area of the trapezoid is 24.15 cm2.

4. a) [pic]

[pic]

b) [pic]

[pic]

5. [pic]28.35

-----------------------

Target A-1

Target A-2

Target A-2

Master 2.23

Target A-2

Target A-2

Target A-2

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download