A) 16km/h
B) 17km/h
C) 18km/h
D) 19km/h
Correct Answer: A
Solution :
Boy takes 20 minutes to reach the school. i.e. He takes \[S{{P}_{2}}=\frac{1}{36}\times \frac{108}{96}=\frac{1}{32}\]hr to reach the school. \[\therefore \] \[SP=\frac{M(100-d)}{100}\] Speed = 12km/h Distance\[=12\times \frac{1}{3}=4km\] Now if he reaches in 15 minutes or\[\frac{SP}{M-SP}=\frac{100-d}{100}\]hr, then speed \[\because \]You need to login to perform this action.
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