Answers

2014-07-21T22:30:10+05:30
Let s be the distance covered in 1 second and r be the distance covered in 3 second 
therefore s/r=(1)^2/(3)^2
                      =1/9
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formula is snth =u+n/2(a-1/2)
i think 7/13
in next page i solve it with long process ,you can see.ans is 1:5
2014-07-21T22:48:55+05:30
For first second let distance covered be v and for 3 sec it be u
v=1/2(a-1/2)
u=3/2(a-1/2)
dividing 1 by 2
v/u=1/3
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