Answer:
6
Step-by-step explanation:
Deisha's build rate = 1 fence per 15 hours = 1/15 fences per hour
Travis's build rate = 1 fence per 12 hours = 1/12 fences per hour
Working together, their combined rate is 1/15 + 1/12 = 3/20 fences per hour
So it takes them 20/3 = 6 2/3 hours per fence
You can say 1/2 = 8/16 so the answer is : 9/16 + 8/16 = 17/16 = 1.06 :))
i hope this is helpful
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