Problem: A and B move uniformly along two straight paths intersecting at right angles in point O. When A is at O,B is 500 yards short of O. In 2 minutes they are equidistant from O, and in 8 minutes more they are again equidistant from O. Then the ratio of A's speed to B's speed is:
Answer Choices:
A. 4:5
B. 5:6
C. 2:3
D. 5:8
E. 1:2
Solution:
Let rAβ represent the speed of A, and let rBβ represent the speed of B.
rBβxβ=2,rAβ500βxβ=2,x=2rBβ
β΄rAβ500β2rBββ=2,rAβ+rBβ
=250
rBβ500βx+yβ=8,rAβyβ500+xβ=8
βyβ500+x=8rAβy+500βx=8rBββ}β2y=8(rAβ+rBβ)=8β
250y=1000ββ
8rBβ=1000+500β2rBβ,rBβ=150β΄rAβ=100β΄rAβ:rBβ=2:3