shashank.ism wrote:Two boats start from the opposite banks of a river simultaneously. They meet at a distance of 410 m from one of the banks and continue sailing further till they reach the opposite banks. They take rest for 1 hr each and start off the return journey. Now they meet at a distance of 230 m from the other bank. Find the distance between the two banks. Note: (Assume that river water is almost still).
a.)750 m
b.) 840 m
c.) 1100 m
d.) 1200 m
e.)1000 m
Let the distance between the banks be x meters
speed of first boat be a and the second boat be b
now, 410/a = x-410/b
b/a = (x-410)/410
Now first boat will reach the other bank in x/a time and second boat will reach there in x/b time and they both take rest for 1 hour
when they meet the second time distance travelled by first boat = x+230
distance travelled by second boat = 2x -230
x+230/a = 2x-230/b
b/a = 2x-230/x+230
x-410/410 = 2x-230/x+230
Now, I would substitute the answers and my luck 1000 comes out to work perfectly
{well purists (I have been seeing many of them lately)can solve the quadratic equation and find out}
Last edited by
ajith on Sat Feb 06, 2010 5:52 am, edited 1 time in total.
Always borrow money from a pessimist, he doesn't expect to be paid back.