Angela painted 3/8 of the room and Todd painted 2/5 of the same room how much of the room is left to paint?

31/40. Cannot be simplified

Start by getting the fractions to have the same denominator by finding the Least Common Multiple of 5 and 8

LCM of 5 and 8 is 40

write the fractions in those terms:

3/8 = 15/40

2/5 = 16/40

add them together to get the total space painted:

15/40 + 16/40 = 31/40

The entire room space is 1, so the room still left to paint is:

1 - 31/40 = 9/40