A boy can reach a certain place in 15 hours. If he reduces his speed by 1/30th, he goes 4 km less in that time. Find his speed. Choose the correct choice from the following options.
A) 4 km/hr.	B) 6 km/hr	C) 8 km/hr	D) 14 km/hr	E) None of these
Explanation :   Solution: Let the speed be x km/hr. then,   15x - (15 * 29x/30) = 4   =&gt; 30x-29x = 4*2   =&gt; x = 8 km/hr.   Answer : 8 km/hr
<result>C</result>
A boy can reach a certain place in 15 hours. If he reduces his speed by 1/30th, he goes 4 km less in that time. Find his speed.