Iris completes of the gymnasium floor in of an hour. To find out how long it will take her to complete the entire floor, we can set up a proportion.
If of the floor takes of an hour, we can find the time to complete whole floor by scaling.
Let be the time (in hours) it takes her to complete the entire floor. Since of the floor takes of an hour, we can set up the equation:
Using cross-multiplication, we can write:
Now, we can solve for :
- Multiply both sides by 3 to eliminate the fraction:
- Divide both sides by 2:
Therefore, it will take Iris hour to complete the entire floor.
In terms of minutes, hour is equal to 30 minutes.
Thus, the answer is:
It will take Iris 30 minutes to complete the entire floor.