By travelling at 30 kmph, a person reaches his destination on time. He covered two-third the total distance in one-third of the total time. What speed should he maintain for the remaining distance to reach his destination on time? Choose the correct choice from the following answers:
A) 19 kmph	B) 15 kmph	C) 12 kmph	D) 20 kmph	E) 23 kmph
Let the time taken to reach the destination be 3x hours. Total distance = 30 * 3= 
<gadget id="calculator">30 * 3</gadget>
<output>90</output>
90x km   He covered 2/3 * 90= 
<gadget id="calculator">2/3 * 90</gadget>
<output>60</output>
60x km in 1/3 * 3x= x hours So, the remaining 30x km, he has to cover in 2x hours. Required speed = 30x/2x   =15 kmph.   Answer: 15 kmph30 /2= 
<gadget id="calculator">30 /2</gadget>
<output>15</output>
15 kmph.   Answer: 15 kmph
<result>B</result>
By travelling at 30 kmph, a person reaches his destination on time. He covered two-third the total distance in one-third of the total time. What speed should he maintain for the remaining distance to reach his destination on time?