Practice the problems of Math in Focus Grade 5 Workbook Answer Key Chapter 9 Practice 1 Multiplying Decimals to score better marks in the exam.

## Math in Focus Grade 5 Chapter 9 Practice 1 Answer Key Multiplying Decimals

**Multiply. Write the product as a decimal.**

Example

2 × 0.3 = 2 × __3__ tenths

= __6__ tenths

__0.6__

So, 2 × 0.3 = __0.6__

Question 1.

5 × 0.6 = 5 × ____ tenths

= ___ tenths

= ____ or ____

So, 5 × 0.6 = ____

Answer:

5 × 0.6 = 5 × 6 tenths

= 30 tenths

= 3.0 or 3

So, 5 × 0.6 = 3

Explanation:

To multiply a decimal number by a decimal number,

we first multiply the two numbers ignoring the decimal points and then;

place the decimal point in the product in such a way that;

decimal places in the product is equal to the sum of the decimal places in the given numbers.

Question 2.

7 × 0.8 = 7 × ___ tenths

= ___ tenths

= _____

So, 7 × 0.8 = ___

Answer:

7 × 0.8 = 7 × 8 tenths

= 56 tenths

= 5.6

So, 7 × 0.8 = 5.6

Explanation:

To multiply a decimal number by a decimal number,

we first multiply the two numbers ignoring the decimal points and then;

place the decimal point in the product in such a way that;

decimal places in the product is equal to the sum of the decimal places in the given numbers.

Question 3.

10 × 0.4 = 10 × ___ tenths

= ___ tenths or

= ___ or ___

So, 10 × 0.4 = ___

Answer:

10 × 0.4 = 10 × 4 tenths

= 4 tenths or

= 4.0 or 4

So, 10 × 0.4 = 4

Explanation:

To multiply a decimal number by a decimal number,

we first multiply the two numbers ignoring the decimal points and then;

place the decimal point in the product in such a way that;

decimal places in the product is equal to the sum of the decimal places in the given numbers.

**Multiply. Write the product as a decimal.**

Example

3 × 0.03 = 3 × __3__

= __9__ hundredths

= __0.09__

So, 3 × 0.03 = __0.09__

Question 4.

5 × 0.02 = 5 × ___ hundredths

= ____ hundredths

= ___ or _____

So, 5 × 0.02 = ____

Answer:

5 × 0.02 = 5 × 2 hundredths

= 10 hundredths

= 10/100 or 0.1

So, 5 × 0.02 = 0.1

Explanation:

To multiply decimals, first multiply as if there is no decimal.

Next, count the number of digits after the decimal in each factor.

Finally, when only one factor has decimal place value,

the product will have as many decimal place values as that one factor.

Question 5.

7 × 0.07 = 7 × ___ hundredths

= ____ hundredths

= ___ or _____

So, 7 × 0.07 = ____

Answer:

7 × 0.07 = 7 × 7 hundredths

= 49 hundredths

= 49/100 or 0.49

So, 7 × 0.07 = 0.49

Explanation:

To multiply decimals, first multiply as if there is no decimal.

Next, count the number of digits after the decimal in each factor.

Finally, when only one factor has decimal place value,

the product will have as many decimal place values as that one factor.

Question 6.

6 × 0.12 = 6 × ___ hundredths

= ____ hundredths

= ___

So, 6 × 0.12 = ____

Answer:

6 × 0.12 = 6 × 12 hundredths

= 72 hundredths

= 0.72

So, 6 × 0.12 = 0.72

Explanation:

To multiply decimals, first multiply as if there is no decimal.

Next, count the number of digits after the decimal in each factor.

Finally, when only one factor has decimal place value,

the product will have as many decimal place values as that one factor.

**Follow the steps to multiply 2.6 by 3. Fill in the blanks.**

Question 7.

Multiply the tenths by 3.

3 × 6 tenths = _18_ tenths

Regroup the tenths.

18___ tenths = _1__ one and __6_ tenths

Step 2

Multiply the tenths by 3.

3 × 2 ones = _6__ ones

Add the ones.

_6__ ones + _1_ one = _7_ ones

So, 3 × 2.6 = _7.8__

**Multiply.**

Question 8.

Answer: 2.4

Explanation:

Multiply the tenths by 8.

8 × 3 tenths = 24 tenths

Regroup the tenths.

24 tenths = 2 one and 4 tenths

Step 2

Multiply the tenths by 8.

8 × 0 ones = 0 ones

Add the ones.

0 ones + 2 one = 2 ones

So, 0.3 × 8 = 2.4

Question 9.

Answer: 10.4

Explanation:

Multiply the tenths by 4.

4 × 6 tenths = 24 tenths

Regroup the tenths.

24 tenths = 2 one and 4 tenths

Step 2

Multiply the tenths by 4.

4 × 2 ones = 8 ones

Add the ones.

8 ones + 2 one = 10 ones

So, 2.6 × 4 = 10.4

Question 10.

Answer: 39.5

Explanation:

Multiply the tenths by 5.

5 × 9 tenths = 45 tenths

Regroup the tenths.

45 tenths = 4 one and 5 tenths

Step 2

Multiply the tenths by 5.

5 × 7 ones = 35 ones

Add the ones.

35 ones + 4 one = 39 ones

So, 7.9 × 5 = 39.5

Question 11.

Answer: 86.8

Explanation:

Multiply the tenths by 7.

7 × 4 tenths = 28 tenths

Regroup the tenths.

28 tenths = 2 one and 8 tenths

Step 2

Multiply the tenths by 5.

7 × 12 ones = 84 ones

Add the ones.

84 ones + 2 one = 86 ones

So, 12.4 × 7 = 86.8

Question 12.

Step 1

Answer: 8.76

Explanation:

Multiply the hundredths by 6.

6 × 6 hundredths =36 hundredths

Regroup the tenths.

36 hundredths = 3 tenths and 6 hundredths

Step 2

Multiply the tenths by 6.

6 × 4 tenths = 24 tenths

Add the tenths.

24 tenths + 3 tenths = 27 tenths

Regroup the tenths.

27 tenths = 2 ones and 7 tenths

Step 3

Multiply the ones by 6.

6 × 1 ones = 6 ones

Add the ones.

6 ones + 2 ones = 8 ones

So, 6 × 1.46 = 8.76

**Multiply.**

Question 13.

Answer: 50.07

Explanation:

Multiply the hundredths by 5.

5 × 7 hundredths =35 hundredths

Regroup the tenths.

35 hundredths = 3 tenths and 5 hundredths

Step 2

Multiply the tenths by 5.

5 × 0 tenths = 0 tenths

Add the tenths.

0 tenths + 3 tenths = 3 tenths

Regroup the tenths.

3 tenths = 0 ones and 3 tenths

Step 3

Multiply the ones by 6.

5 × 10 ones = 50 ones

Add the ones.

50 ones + 0 ones = 50 ones

So, 5 × 10.07 = 50.35

Question 14.

Answer: 3

Explanation:

Multiply the tenths by 4.

4 × 5 tenths = 20 tenths

Regroup the tenths.

20 tenths = 2 one and 0 tenths

Step 2

Multiply the tenths by 4.

4 × 7 ones = 28 ones

Add the ones.

28 ones + 2 one = 2 ones

So, 0.75 × 4 = 3

Question 15.

Answer: 27.54

Explanation:

Multiply the hundredths by 9.

9 × 6 hundredths =54 hundredths

Regroup the tenths.

54 hundredths = 5 tenths and 4 hundredths

Step 2

Multiply the tenths by 9.

9 × 0 tenths = 0 tenths

Add the tenths.

0 tenths + 54 tenths = 54 tenths

Regroup the tenths.

54 tenths = 5 ones and 4 tenths

Step 3

Multiply the ones by 9.

9 × 3 ones = 27 ones

Add the ones.

27 ones + 0 ones = 27 ones

So, 9 × 3.06 = 27.54

Question 16.

Answer: 121.92

Explanation:

Multiply the hundredths by 8.

8 × 4 hundredths =32 hundredths

Regroup the tenths.

32 hundredths = 3 tenths and 2 hundredths

Step 2

Multiply the tenths by 8.

8 × 2 tenths = 16 tenths

Add the tenths.

16 tenths + 3 tenths = 3 tenths

Regroup the tenths = 19

Step 3

Multiply the ones by 8.

8 × 15 ones = 120 ones

Add the ones.

120 ones + 1 ones = 121 ones

So, 8 × 15.24 = 121.92

Question 17.

4 × 2.08 = ___

Answer: 8.32

Explanation:

Multiply the hundredths by 4.

4 × 8 hundredths =32 hundredths

Regroup the tenths.

32 hundredths = 3 tenths and 2 hundredths

Step 2

Multiply the tenths by 4.

4 × 0 tenths = 16 tenths

Add the tenths.

0 tenths + 3 tenths = 3 tenths

Step 3

Multiply the ones by 4.

4 × 2 ones = 8 ones

Add the ones.

8 ones + 32 ones = 8.32 ones

So, 4 × 2.o8 = 8.32

Question 18.

3 × 3.29 = ___

Answer: 9.87

Explanation:

Multiply the hundredths by 3.

9 × 3 hundredths =27 hundredths

Regroup the tenths.

27 hundredths = 2 tenths and 7 hundredths

Step 2

Multiply the tenths by 3.

3 × 2 tenths = 6 tenths

Add the tenths.

6 tenths + 0 tenths = 6 tenths

Regroup the tenths

6 tenths + 2 tenths = 8 tenths

Step 3

Multiply the ones by 6.

6 × 3 ones = 18 ones

Add the ones.

8 ones + 1 ones = 9 ones

So, 3 × 3.29 = 9.87

Question 19.

7 × 5.71 = ___

Answer: 39.97

Explanation:

Multiply the hundredths by 7.

1 × 7 hundredths =7 hundredths

Regroup the tenths.

7 hundredths = 0 tenths and 7 hundredths

Step 2

Multiply the tenths by 7.

7 × 7 tenths = 49 tenths

Add the tenths.

49 tenths + 0 tenths = 49 tenths

Regroup the tenths

49 tenths = 4 ones and 7 tenths

Step 3

Multiply the ones by 7.

5 × 7 ones = 35 ones

Add the ones.

35 ones + 4 ones = 39 ones

So, 7 × 5.71 = 39.97

Question 20.

6 × 4.81 = ___

Answer: 28.86

Explanation:

Multiply the hundredths by 6.

1 × 6 hundredths =6 hundredths

Regroup the tenths.

6 hundredths = 0 tenths and 6 hundredths

Step 2

Multiply the tenths by 6.

8 × 7 tenths = 48 tenths

Add the tenths.

48 tenths + 0 tenths = 48 tenths

Regroup the tenths

48 tenths = 4 ones and 8 tenths

Step 3

Multiply the ones by 6.

4 × 6 ones = 24 ones

Add the ones.

24 ones + 4 ones = 28 ones

So, 6 × 4.81 = 28.81

Question 21.

9 × 7.46 = ___

Answer: 67.14

Explanation:

Multiply the hundredths by 9.

9 × 6 hundredths =54 hundredths

Regroup the tenths.

54 hundredths = 5 tenths and 4 hundredths

Step 2

Multiply the tenths by 9.

9 × 4 tenths = 36 tenths

Add the tenths.

36 tenths + 5 tenths = 41 tenths

Regroup the tenths

41 tenths = 4 ones and 1 tenths

Step 3

Multiply the ones by 9.

9 × 7 ones = 63 ones

Add the ones.

63 ones + 4 ones = 67 ones

So, 9 × 7.46 = 67.14

Question 22.

8 × 6.52 = ___

Answer: 52.16

Explanation:

Multiply the hundredths by 8.

8 × 2 hundredths =16 hundredths

Regroup the tenths.

16 hundredths = 1 tenths and 6 hundredths

Step 2

Multiply the tenths by 8.

8 × 5 tenths = 40 tenths

Add the tenths.

40 tenths + 1 tenths = 41 tenths

Regroup the tenths

41 tenths = 4 ones and 1 tenths

Step 3

Multiply the ones by 8.

8 × 6 ones = 48 ones

Add the ones.

48 ones + 4 ones = 52 ones

8 × 6.52 = 52.16

**Write the correct decimal in each box.**

Example

Question 23.

Answer: 21.38

Explanation:

0.46 x 3

3 × 0.46 = 3 × 46 hundredths

= 138 hundredths

= 1.38

So, 3 × 0.46 = 1.38

20+1.38 = 21.38

Question 24.

Answer:20.04

Explanation:

6 x 0.84

6 × 0.84 = 6 × 84 hundredths

= 504 hundredths

= 5.04

So, 6 × 0.84 = 5.04

15+5.04 = 20.04

Question 25.

Answer: 31.4

Explanation:

5×1.28

5 × 1.28 = 5 ×128 hundredths

= 640 hundredths

= 6.40

So, 5 × 1.28 = 6.40

25+6.40 = 31.4