The efficiency : 95%
Further explanation
Efficiency : the ratio between output and input work
In general, the value of the output of a machine is less than the value of the input because of the frictional force in the machine.
The greater the efficiency of the engine, the better the machine
Can be formulated :
[tex]\tt E=\dfrac{W_{out}}{W_{in}}\times 100\%[/tex]
w output = 190 J
W input = 200 J
The efficiency :
[tex]\tt E=\dfrac{190}{200}\times 100\%=95\%[/tex]
