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, 2024

Algebra Difficulty 1.2 Junior Find the answer Canada

Katie completed two laps of a track without stopping. The first
lap took $3$ minutes and $45$
seconds, and the second lap took $4$ minutes and $35$ seconds. What was her total
time?

$8$ minutes $30$ seconds
$7$ minutes $50$ seconds
$8$ minutes $50$ seconds
$8$ minutes $20$ seconds
$7$ minutes $40$ seconds

Your answer

A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.

Solution

Katie’s total time is equal to the sum of $3$ minutes and $45$ seconds and $4$ minutes and $35$ seconds. Adding $45$ seconds and $35$ seconds, we get $45+35=80$ seconds. Since there are $60$ seconds in $1$ minute, then $80$ seconds is equal to $1$ minute and $20$ seconds. Thus, Katie’s total time was
$3+4+1=8$ complete minutes plus $20$ seconds, for a total of $8$ minutes and $20$ seconds.

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.