Question 1003390
First calculate the time worked in the office. Eight hours is the difference between 5:30pm (17:30) and 9:30am. But subtract half an hour from that because of the lunch break. So seven and a half hours is the time worked in the office.

Without simplifying, the ratio would be {{{.5/7.5}}}

The ratio can be reduced by .5, so the final answer is {{{1/15}}}