This handy Math in Focus Grade 3 Workbook Answer Key Chapter 16 Practice 4 Subtraction of Time provides detailed solutions for the textbook questions.

## Math in Focus Grade 3 Chapter 16 Practice 4 Answer Key Subtraction of Time

**Subtract**

**Example**

Question 1.

So, 8 h 20 min – 7 h 15 min

= _______ h _________ min.

______ h – ______ h = ______ h

______ min – ______ min = ______ min

______ h – ______ min = ______ h ______ min

Answer: 1 hour 5 minutes.

We measure time in hours, minutes, and seconds. There are 60 minutes in an hour and 60 seconds in a minute.

Follow these steps:

1. Subtract the hours

2. Subtract the minutes

3. If the minutes are negative, add 60 to the minutes and subtract 1 from hours.

Explanation:

Step 1: Subtract the hours.

=8hours-7hours

=1 hour

Step 2: Subtract the minutes.

=20min-15min

=5 min

Hence, the resultant from Step 1 and Step 2 together is the answer (1hour 5minutes).

Question 2.

So, 4 h 35 min – 1 h 15 min

= _______ h _________ min.

______ h – ______ h = ______ h

______ min – ______ min = ______ min

______ h – ______ min = ______ h ______ min

Answer:3 hour 20 minutes

We measure time in hours, minutes, and seconds. There are 60 minutes in an hour and 60 seconds in a minute.

Follow these steps:

1. Subtract the hours

2. Subtract the minutes

3. If the minutes are negative, add 60 to the minutes and subtract 1 from hours.

Explanation:

Step 1: Subtract the hours.

=4hours-1hours

=3 hour

Step 2: Subtract the minutes.

=35min-15min

=20 min

Hence, the resultant from Step 1 and Step 2 together is the answer (3hour 20minutes).

Question 3.

So, 3 h 55 min – 2 h 30 min

= _______ h _________ min.

______ h – ______ h = ______ h

______ min – ______ min = ______ min

______ h – ______ min = ______ h ______ min

Answer: 1 hour 25 minutes.

We measure time in hours, minutes, and seconds. There are 60 minutes in an hour and 60 seconds in a minute.

Follow these steps:

1. Subtract the hours

2. Subtract the minutes

3. If the minutes are negative, add 60 to the minutes and subtract 1 from hours.

Explanation:

Step 1: Subtract the hours.

=3hours-2hours

=1 hour

Step 2: Subtract the minutes.

=55min-30min

=25 min

Hence, the resultant from Step 1 and Step 2 together is the answer (1hour 25minutes).

**Subtract**

Question 4.

Answer: 30 minutes

Explanation:

We measure time in hours, minutes, and seconds. There are 60 minutes in an hour and 60 seconds in a minute.

Follow these steps:

1. Subtract the hours

2. Subtract the minutes

3. If the minutes are negative, add 60 to the minutes and subtract 1 from hours.

Here in the question, 2 h 20 min and 1 h 50 min.

Explanation:

Step 1: Subtract the hours.

=2hours-1hours

=1 hour

Step 2: Subtract the minutes.

=20min-50min

=-30 min

The minutes are negative. So follow step 3.

Step 3: add 60 to the minutes and subtract 1 from hours.

=60+20

=80

Subtract 1 from 2

=2-1

=1

Now calculate 1 h 80 min and 1 h 50 min

If we subtract hours 1-1=0

If we subtract min 80-50=30

Hence, the resultant from Step 1 and Step 2 together is the answer (0hour 30minutes).

Question 5.

Answer: 2 h 50 min

Explanation:

Follow these steps:

1. Subtract the hours

2. Subtract the minutes

3. If the minutes are negative, add 60 to the minutes and subtract 1 from hours.

Here in the question, 2 h 20 min and 1 h 50 min.

Explanation:

Step 1: Subtract the hours.

=5hours-2hours

=3 hour

Step 2: Subtract the minutes.

=15min-25min

=-10 min

The minutes are negative. So follow step 3.

Step 3: add 60 to the minutes and subtract 1 from hours.

=60+15

=75

Subtract 1 from 2

=5-1

=4

Now calculate 4 h 75 min and 2 h 25 min

If we subtract hours 4-2=2

If we subtract min 75-25=50

Hence, the resultant from Step 1 and Step 2 together is the answer (2hour 50minutes).

Question 6.

Answer:4 h 15 min

Explanation:

Follow these steps:

1. Subtract the hours

2. Subtract the minutes

3. If the minutes are negative, add 60 to the minutes and subtract 1 from hours.

Here in the question, 6 h 10 min and 1 h 55 min.

Explanation:

Step 1: Subtract the hours.

=6hours-1hours

=5 hour

Step 2: Subtract the minutes.

=10min-55min

=-45 min

The minutes are negative. So follow step 3.

Step 3: add 60 to the minutes and subtract 1 from hours.

=10+60

=70

Subtract 1 from 6

=6-1

=5

Now calculate 5 h 70 min and 1 h 55 min

step 4: If we subtract hours 5-1=4

step 5: If we subtract min 70-55=15

Hence, the resultant from Step 4 and Step 5 together is the answer (4hour 15minutes).

Question 7.

Answer: 4 h 55 min

Explanation:

Follow these steps:

1. Subtract the hours

2. Subtract the minutes

3. If the minutes are negative, add 60 to the minutes and subtract 1 from hours.

Here in the question, 9 h 40 min and 4 h 45 min.

Explanation:

Step 1: Subtract the hours.

=9hours-4hours

=5 hour

Step 2: Subtract the minutes.

=40min-45min

=-5 min

The minutes are negative. So follow step 3.

Step 3: add 60 to the minutes and subtract 1 from hours.

=40+60

=100

Subtract 1 from 9

=9-1

=8

Now calculate 8 h 100 min and 4 h 45 min

step 4: If we subtract hours 8-4=4

step 5: If we subtract min 100-45=55

Hence, the resultant from Step 4 and Step 5 together is the answer (4hour 55minutes).

**Solve.**

Question 8.

Rita takes 3 hours 5 minutes to sew a dress. Tara takes 2 hours 40 minutes to sew a similar dress. How much longer does Rita take to sew the dress than Tara?

Answer: 25 minutes longer Tita take to sew the dress than Tara.

The time Rita takes to sew a dress=3 h 5 minutes.

The time Tara takes to sew a dress=2 h 40 minutes.

Follow these steps:

1. Subtract the hours

2. Subtract the minutes

3. If the minutes are negative, add 60 to the minutes and subtract 1 from hours.

Here in the question, 3 h 5 min and 2 h 40 min.

Explanation:

Step 1: Subtract the hours.

=3hours-1hours

=1 hour

Step 2: Subtract the minutes.

=5min-40min

=-35 min

The minutes are negative. So follow step 3.

Step 3: add 60 to the minutes and subtract 1 from hours.

=60+5

=65

Subtract 1 from 3

=3-1

=2

Now calculate 2 h 65 min and 2 h 40 min

step 4: If we subtract hours 2-2=0

step 5: If we subtract min 65-40=25

Hence, the resultant from Step 4 and Step 5 together is the answer (0hour 25minutes).