Each day Heather drinks 2/5 cup of juice in the morning afternoon when she gets home from school. How many days will it take Heather to drink 3 cups of juice?

Jan 23, 2018

It’ll take Heather $7.5$ days, which can be rounded to $8$ days.

Explanation:

Let $d$ denote the number of days it will take Heather to drink $3$ cups of juice.

So, we have the equation: $\setminus \frac{2}{5} d = 3$.

We can isolate for $d$ by multiplying both sides by the reciprocal of $d$’s coefficient:

$\cancel{\setminus \frac{5}{2}} \setminus \cdot \cancel{\setminus \frac{2}{5}} d = 3 \setminus \cdot \setminus \frac{5}{2}$

$\setminus \rightarrow d = \setminus \frac{15}{2}$

This means it will take Heather $7.5$ days to drink $3$ cups of juice, which we can round up to $8$ for simplicity’s sake.