Transcript Solving problems involving time

Time
5th Grade Strategies for Your
Toolbox to Help Solve Problems
Involving Time
Let’s Review – Counting Minutes
 There are 12 numbers around the face of
a clock.
 Each number represents a set number of
minutes past the hour.
So, to figure out the
number of minutes,
you can count by 5s.
How to Tell Time to the Minute
1.Count the
minutes
by 5.
2.Then
count the
minutes
by ones.
5
10
15
20
21
22
23
How to Tell Time to the Minute
3. Now read
the hour
hand.
4. Then say
1:23 or
23
minutes
after 1.
5
10
15
20
21
22
23
Let’s Review – Counting Minutes
 Example: When the minute hand is on the 6,
it is 30 minutes past the hour
 Tip: Multiply 6 x 5 = 30; the minute is on the
6 and we are counting by 5s
So, to figure out the
number of minutes,
you can count by 5s.
Practice Calculating Minutes
• If the minute hand is on the
3, how many minutes past
the hour is it?
15
• How about on the 7?
35
Practice Calculating Minutes
• How about on the 11?
55
Multiply 11 x 5 = 55 minutes
• How about on the 9?
45
Multiply 9 x 5 = 45 minutes
Are there any questions???
You are doing a great job!!
Let’s continue…
Telling Time Lingo
• When the minute hand rotates around one
time, a hour has past.
• When the minute hand points to 12, it is
exactly an hour. Whatever number the hour
hand points to is the hour.
• When the hour hand is between the hours,
we can say it is “half-past” the hour.
• When the hour hand points to the 3, it has
gone a quarter way around; we can say it is
“quarter-past” the hour.
Telling Time Lingo
• When the hour hand points to the 9,
it has gone three quarters around;
we can say it is a “quarter ‘to” the
hour.
Different Ways to Say the Time
o'clock
quarter
past
quarter
to
half past
• An hour = 60
minutes &
therefore can
be divided
into 4 parts.
• The parts are
divided by the
0, 15, 30, &
45 minute
marks as
shown in the
picture.
Different Ways to Say the Time
o'clock
quarter
to
half past
• Each of the 4
parts are called
quarters.
• When the # of
min. is greater
than 30, instead
quarter of saying the #
past
of min. after the
hour, you can
say the # of min.
before the next
hour, or the # of
min. to the hour.
Different ways to say the
same time…
We could say that it is
3:45
o'clock
quarter
to
We could say that
it’s a quarter to 4.
The hour hand is
between 3 and 4.
quarter
The
past
minute hand
is three quarters
around the clock.
half past
We are almost finished
• You are
amazing……..I
knew you could
do it.
What is elapsed time?
• Elapsed time is the time or difference
between a beginning time and an ending
time.
• Finding elapsed time is an important skill
in everyday life.
• Determining elapsed time requires
understanding how to read a clock and
understanding how we measure time.
Elapsed Time
Write the time it will be in 2 hours?
5:10
3:10 _____
7:35
5:35 _____
2:04
12:04 _____
Write the time it will be in 4 hours?
11:11
7:11 _____
10:42
6:42 _____
3:05
11:05 _____
Practice Finding Elapsed Time
• 4:00 to 4:30
30 min.
• 7:30 to 8:10
50 min
• 8:20 to 8:25
5 min.
• 3:55 to 4:00
5 min.
11:00 to 11:45
45 min.
9:15 to 10:20
1 hr 5 min
4:10 to 5:15
1 hr 5 min
12:25 to 2:30
2 hrs 5 min.
5:35
12:50
1 minute = 60 seconds
5 minutes 43
seconds
Divide 343 seconds
by 60 seconds
343 ÷ 60 = 5 R 43
2
15 minutes = 1 quarter hour
1 half hour = 30 minutes
1 half hour = 2 quarter hours
4 qtr hrs ÷ 2 qtr hrs = 2 half hrs
52
1 year = 52 weeks
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