If the power of an engine grows by 10% when the number of its cylinders is increased by one, which of the following is closest to the ratio of the power of a 9-cylinder engine to that of a 12-cylinder engine?
# 0.69
# 0.71
# 0.72
# 0.75
# 0.78
Please give detailed explanations.
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power of an engine
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uptowngirl92
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IMO: 0.75
power of 9 cylinder = X
power of 10 cylinder = X(1.1)
power of 11 --- = X(1.1)(1.1)
power of 12 -- = X(1.1)(1.1)(1.1)
ratio = 1/(1.1)^3
==> 1/1.331
==> 100/133 ==> 0.75
power of 9 cylinder = X
power of 10 cylinder = X(1.1)
power of 11 --- = X(1.1)(1.1)
power of 12 -- = X(1.1)(1.1)(1.1)
ratio = 1/(1.1)^3
==> 1/1.331
==> 100/133 ==> 0.75
