Machine E can produce x units in 3/4 of the time it takes machine N to produce x units. Machine N can produce x units in 2/3 the time it takes machine O to produce x units. If all three machines are working simultaneously, what fraction of the total output is produced by machine N?  Choose the correct answer: A) 1/2 B) 1/3 C) 4/13 D) 8/29 E) 6/33
Let the following be true:   E makes x in time t   Then the following follows:   N makes x in 4t/3   O makes x in 3/2(4t/3) = 2t   M:N:O = 1:4/3:2=3:4:6   So N=4/(3+4+6)=4/13=4/13
<result>C</result>
Machine E can produce x units in 3/4 of the time it takes machine N to produce x units. Machine N can produce x units in 2/3 the time it takes machine O to produce x units. If all three machines are working simultaneously, what fraction of the total output is produced by machine N?