Lesson 12 Hours, Minutes, and Seconds

Warm-up What Do You Know About …?

What do you know about 1 hour?

The table shows how Mai spends the time she is awake on a school day.

Complete the table to show how many minutes Mai spends on each activity. Be prepared to explain or show your reasoning.
activity
hours
minutes
morning routine
$1$
getting to school
$\frac{1}{2}$
time at school
$8$
getting home from school
$\frac{3}{4}$
homework and reading
$1 \frac{1}{2}$
playing and family time
$2$
bedtime routine
$\frac{1}{4}$
How many hours does Mai spend at school? How many minutes is that? Explain or show how you know.
How many minutes does Mai sleep on a school night? Explain or show your reasoning.

Diego set a timer to make sure that things are not done for too long or too short an amount of time.

Complete the table with the number of seconds for each activity. Be prepared to explain your reasoning.
activity
minutes
seconds
brushing teeth
$2$
showering
$3$
heating a cup of milk in the microwave
$\frac{1}{2}$
break during homework time
$5$
quick workout
$10$
daily reading
$30$
Diego noticed that on a television channel, commercial breaks are often between $1 \frac{1}{2}$ and $2 \frac{1}{2}$ minutes long each. How long are they in seconds? Explain or show your reasoning.
Diego’s workout starts with 4 minutes of warm-up and stretching, followed by 100 seconds of jumping jacks.

If he works out for 10 minutes exactly, how many more seconds are left in his workout?

activity	minutes	seconds
brushing teeth	$2$
showering	$3$
heating a cup of milk in the microwave	$\frac{1}{2}$
break during homework time	$5$
quick workout	$10$
daily reading	$30$

Diego said it took him 1,800 seconds to get home from school yesterday. Lin thinks he is exaggerating.

It took Diego $\frac{1}{2}$ hour to get home from school yesterday. How many minutes is that? Explain your reasoning.
How many seconds is that? Explain or show your reasoning.
Was Diego’s statement correct or is he exaggerating?