<PRE><B>Question 920853</B>
1) let 2x be the time Katrina mows the lawn, then
1/x + 1/2x = 1/2.5
2.5x is GCD
2.5 + 2.5/2 = x
multiply both sides of = by 2
5 + 2.5 = 2x
so 2x = 7.5 hours for Katrina to mow lawn, therefore
x = 3.75 hours for Brooks to mow lawn
2) let x be time for Gustov to paint room, then
1/x + 1/5 = 1/3
15x is GCD
15 + 3x = 5x
15 = 2x
x = 7.5 hours for Gustov to paint the room
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