Maths Olympiad Prep

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, 2022

Algebra Difficulty 1.1 Junior Find the answer Canada

Gauravi walks every day. One Monday, she walks 500 m. On each day
that follows, she increases her distance by 500 m from the previous day.
On what day of the week will she walk exactly 4500 m?

Pick one

Solution

From the day on which she walks 500 m to the day on which she
walks 4500 m, Gauravi increases her distance by $(4500\$(4500\text{} m}) - (500(500\text{} m}) = 40004000\text{}
m}$.

Since Gauravi increases her distance by 500 m each day, then it takes
$4000 m500\$\dfrac{4000\text{ m}}{500\text{}} m}} =
8$ days to increase from 500 m to 4500 m.

Starting from Monday and counting forward by 8 days (which is 1 week and
1 day) gets to Tuesday, and so Gauravi walks exactly 4500 m on a
Tuesday.

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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.