Question 729664
1/4+1/X=1/1.5
1/X=1/1.5-1/4
1/X=(4-1.5)/(1.5*4)
1/X=2.5/6
2.5X=6
X=6/2.5
X=2.4 HOURS FOR KEN WORKING ALONE.
PROOF:
1/4+1/2.4=1/1.5
(2.4+4)/4*2.4=1/1.5
6.4/9.6=1/1.5
9.6*1=6.4*1.5
9.6=9.6