Two crews were assigned the job of setting a total of 960 conduit hangers. By the time the job was completed, one crew had set only 7/8 as many conduit hangers as the other crew. How many conduit hangers were set by the slower group?

2 answers

so let the amounts be x and 7/8 x
x + 7/8 x = 960
15/8 x = 960
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Were did you get 15/8 from?