Question

A swimming pool is open for 7 1/2 hours a day. The pool keeps one life guard on duty at a time, and each life guard shift is 1 1/2 hours long. How many shift per day?

Answer 1

There are 5 shifts per day

Solution:

Given that, A swimming pool is open for
`7(1)/(2)` hours a day

The pool keeps one life guard on duty at a time

Each life guard shift is
`1(1)/(2)` hours long

To find: Number of shifts per day

From given,

`\text{ Number of hours } =7(1)/(2) = (2 * 7 + 1)/(2) = (15)/(2)`

`\text{Each life guard shift }= 1(1)/(2) = (3)/(2) \text{ hours }`

Therefore, number of shifts per day is found by dividing total number of hours by hours of each life guard shift

`\text{Number of shifts per day } = \frac{\text{Total number of hours}}{\text{each life guard shift }}`

Substituting the values we get,

`\text{Number of shifts per day } = ((15)/(2))/((3)/(2))\\\\\text{Number of shifts per day } = (15)/(2) * (2)/(3)\\\\\text{Number of shifts per day } = 5`

Thus there are 5 shifts per day