Posted by
**patti help** on
.

one task takes 7 mins

second task takes 12 min

third task takes 21 nin

how long dids the 3 tasks take, as a fraction of a hour

7/30+12/30+21/30=40/30 =1 1/3 hr

is that right?

no 2/3

Prinness is correct. There are 60 minutes (not 30) in an hour. So -- your answer would be 40/60 = 2/3 hour.