Problem: Olympia listened to some old records.
The first song lasted 2 minutes and 12 seconds, the
the second lasted 2 minutes and 16 seconds, the third 2
minutes and 18 seconds, and the fourth 3 minutes
and 4 seconds. Use mental math to determine the
total playing time for all four records.
Solution:
- Song 1 duration time: 2 minutes and 12 seconds.
- Song 2 duration time: 2 minutes and 16 seconds.
- Song 3 duration time: 2 minutes and 18 seconds.
- Song 4 duration time: 3 minutes and 4 seconds
Total playing time =
(2 minutes and 12 seconds)+ (2 minutes and 16 seconds)+(2 minutes and 18 seconds)+(3 minutes and 4 seconds).
This is equivalent to say:
Total playing time = 3x 2 minutes + 3 minutes + (12 + 16+18+4) seconds
= 6 minutes + 3 minutes + 50 seconds.
= 9 minutes + 50 seconds.
Then the correct answer is:
The total playing time is 9 minutes and 50 seconds.