A spider climbed \(62\frac{1}{2}\%\) of the height of a pole in the first hour, and in the next hour it covered \(12\frac{1}{2}\%\) of the remaining height. If the pole is 192 m high, what distance did the spider climb in the second hour?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → 9 m
The second percentage is taken of the height still left, not of the whole pole. \(62\frac{1}{2}\%=\frac{5}{8}\) and \(12\frac{1}{2}\%=\frac{1}{8}\).
First hour: \(\frac{5}{8}\times192=120\) m
Height left \(=192-120=72\) m
Second hour: \(\frac{1}{8}\times72=9\) m
In the second hour the spider climbed 9 m.