Question

Mai spends 7 and 3/5 hours in school each day. Her lunch period is 30 minutes long, and she spends a total of 42 minutes switching rooms between classes. The rest of her day is spent in 6 classes that are all the same length. How long is each class?

Answer 1

First, we solve for the number of minutes in 7 and 3/5 hours by multiplying the number by 60 giving us,
                            (7 + 3/5) x (60) = 456 minutes
Spending 30 minutes for lunch will leave her with 426 minutes. Then, spending 42 minutes for switching of classes will finally give her 414 minutes. 

We then divide this value by 6 (for her 6 classes) giving us 69 minutes. Thus, each class is 69 minutes long.