A professional cyclist rides a bicycle that is 92 percent efficient. For every 100 joules of energy he exerts as input work on the pedals, how many joules of output work are used to move the bicycle?

Since Efficiency = 92% = 0.92Efficiency =  (Work Output) / (Work Input)            0.92   =    Wo / 100              Wo  =  0.92 * 100               Wo  =  92 J.Therefore 92J is used to move the bicycle.