Question

(04.05)Marcus painted one-third of his bedroom in fourth-fifths of an hour. At this rate, how long would it take him to paint the entire room?

five-twelfths of an hour
twelve-fifths of an hour
fifteen-fourths of an hour
four-fifteenths of an hour

Answer 1

12/5

Explanation:

1/3 = 4/5

2/3= 8/5

3/3= 12/5

Answer 2

So it took him 4/5 of an hour to paint 1/3
that means there is still 2/3 to go
so that means that he will have two times that time to paint the rest of the room
4/5 = ?
1/3 2/3
using cross multiplication
(4/5)(2/3) = (1/3) (?)
8/15 = 1/3 ?
divide both sides by 1/3
so that will be 8/5
that means it will take 8/5 of an hour to complete the rest

= 12/5 total to do entire room