Jack and Jill went up and down a hill. They started from the bottom and Jack
met jill again 20 miles from the top while returning. Jack completed the race
1 min a head of jill. if the hill is 440 mts high and their speed while down
journey is 1.5 times the up journey. how long it took for the Jack to
complete the race ?  Select the correct option:  A) 10.6 min  B) 11.6 min  C) 12.6 min  D) 13.6 min  E) 14.6 min
Let speed and time of Jack be s1 &amp; t1 &amp; Jill having s2 &amp; t2.   Time taken for Jack to travel 440 miles up and 20 miles down   = Time taken for Jill to travel 440-20= 
<gadget id="calculator">440-20</gadget>
<output>420</output>
420 miles up   440/s1 + 20/1.5s1= 420/s2   68/1.5s1= 420/s2   68s2= 63s1   s2 = 63s1/68 ---(1)   Now from the second given condition- Jack reaches 1 min before Jill. So   t2-t1=1   880/s2 - 880/s1  2- 1= 
<gadget id="calculator"> 2- 1</gadget>
<output>1</output>
1   880/s2 - 880/s1= 1   1/s2 - 1/s2 = 1/880   from equation (1) put value of s2   Solving and putting value of s1 in t1=d/s1 (d=880)   t1 = 12.6 min   ANSWER:12.6 min
<result>C</result>
Jack and Jill went up and down a hill. They started from the bottom and Jack
met jill again 20 miles from the top while returning. Jack completed the race
1 min a head of jill. if the hill is 440 mts high and their speed while down
journey is 1.5 times the up journey. how long it took for the Jack to
complete the race ?