Question 911889
If two oil pipelines can fill a small tank in 30 minutes. Using one of the pipelines would require 45 minutes to fill the tank. How long would it take the second pipeline alone to fill the tank?
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1/45=work rate of one of 2 pipes
1/x=work rate of 2nd pipe
1/30=work rate of 2 pipes working together to fill the tank
sum of indv. work rates=work rate working together
..
{{{1/45+1/x=1/30}}}
{{{1/x=1/30-1/45}}}
lcd:90
90/x=3-2
90/x=1
x=90
How long would it take the second pipeline alone to fill the tank? 90 min