Question 973798
2 people are 2.2 miles apart. they leave same time and walk same direction .
 person A overtakes person B in 11 hours.
 if they walk towards each other , they meet in 1 hour .
 find their speed:
let a = speed of A
let b = speed of B
:
Relative speed walking toward each other is additive
Relative speed walking the same direction is subtractive
:
Write distance equation for each way. Dist = time * speed
11(a - b) = 2.2
1(a + b) = 2.2
divide the  first equation by 11
a - b = .2
a + b = 2.2
---------------Adding eliminates b, find a
2a = 2.4
a = 2.4/2
a = 1.2 mph is A's speed
use the 2nd equation to find b, replace a with 1.2
1.2 + b = 2.2
b = 2.2 - 1.2
b = 1.0 mph is B's speed
:
:
Check this in the 1st original equation
11(1.2 - 1.) = 2.2
11(.2) = 2.2