CEMC Fermat, 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 $(4500\text{ m}) - (500\text{ m}) = 4000\text{ m}$ .

Since Gauravi increases her distance by 500 m each day, then it takes
$\dfrac{4000\text{ m}}{500\text{ m}} = 8$ 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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