Question 890999
At the beginning df a walk, Roberto and Juanita are 2.2 miles apart.
 If they leave at the same time and walk in the same direction, Roberto overtakes Juanita in 11 hours.
 If they walk towards each other the meet in 1 hour.
 What are their speeds?
:
Let r = R's walking speed
let j = J's walking speed
:
When walking the same direction, you subtract their speeds
When walking towards each other you add their speeds
:
Write a distance equation for each scenario
:
11(r-j) = 2.2
and
1(r+j) = 2.2
r + j = 2.2
r = (2.2-j)
In the 1st equation replace r with (2.2-j)
11((2.2-j)-j) = 2.2
11(2.2-2j) = 2.2
24.2 - 22j = 2.2
-22j = 2.2 - 24.2
-22j = -22
j = 1 mph is J's walking speed
:
Find r using the equation r = 2.2-j
r = 2.2 - 1
r = 1.2 mph is R's walking speed
:
:\
Check this by writing the equation when walking towards each other for 1 hr
1.2 + 1.0 = 2.2 mi