Question

Mai spends 7 3/5 hours in school each day. Her lunch period is 1/2 hour long, and she spends a total of 7/10 hour 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?

Please show work!

Answer 1

Lunch: 0.5 Changing rooms: 0.7
7.75 - 1.2 = 6.55
6.55 / 6 = 1.09 hours/class

Answer 2

7 3/5 = 38/7 hours
1/2 hour
7/10 hour

convert them so they all have the same denominators

38/7 = 380/70
1/2 = 35/70
7/10 = 49/70

add 35/70 and 49/70 then subtract from 380/70

35/70 + 49/70 = 84/70
380/70 - 84/70 = 296/70

296/70 divided into 6 classes

296/70 divide 6 = 296/70 x 1/6
= 74/105 x 60 mins
= 42.28571429
each class is approximately 42 mins long