Iris is asked to sweep the gymnasium floor after a basketball game. This requires her to push a sweeper from one end of the gym to the other and repeating the pattern until she has covered the entire floor. She completes 23 of the floor in 13 of an hour. At this rate, how long will it take her to complete the entire floor?(1 poi

1 answer

To determine how long it will take Iris to complete the entire floor, we can use the information given about the portion of the floor she has already completed.

Iris completed \( \frac{2}{3} \) of the floor in \( \frac{1}{3} \) of an hour.

To find out how long it will take her to complete the entire floor, we can set up a proportion:

If \( \frac{2}{3} \) of the floor takes \( \frac{1}{3} \) hours, then \( 1 \) whole floor would take \( x \) hours.

The proportion is:

\[ \frac{2/3 \text{ of the floor}}{\frac{1}{3} \text{ hours}} = \frac{1 \text{ floor}}{x \text{ hours}} \]

Cross-multiplying gives:

\[ 2/3 \cdot x = \frac{1}{3} \]

Now, solve for \( x \):

\[ x = \frac{1}{3} \div \frac{2}{3} = \frac{1}{3} \cdot \frac{3}{2} = \frac{1}{2} \]

Thus, it will take Iris \( \frac{3}{2} \) hours, or 1.5 hours, to complete the entire floor.