Pedro spent 2 1/5 hours on his math himework and half as lomg on his science homework one weekend. If his english and social studies homework took 7/8 as long, how much time did he spent on homework that weekend?

Answer 1

add:
2 1/5 + (1/2)(2 1/5) + (7/8)(2 1/5)
= 11/5 + (1/2)(11/5) + (7/8)(11/5)
= 11/5 + 11/10 + 77/40

take over, the LCD is 40