SOLUTION: If bill rides his bike 3 miles to Fred's house and then walks with Fred the remaining 1 mile to school, it will take him 30 minutes. But if he rides the entire distance, it will ta
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Question 299963: If bill rides his bike 3 miles to Fred's house and then walks with Fred the remaining 1 mile to school, it will take him 30 minutes. But if he rides the entire distance, it will take him only 20 minutes. what is his walking and biking speed?
You can put this solution on YOUR website! If bill rides his bike 3 miles to Fred's house and then walks with Fred the
remaining 1 mile to school, it will take him 30 minutes.
But if he rides the entire distance, it will take him only 20 minutes.
what is his walking and biking speed?
:
let b = biking speed
let w = walking speed
:
Write two time equations; time = dist/speed:
ride and walk equation + =
and
ride only equation =
Cross multiply
b = 4*3
b = 12 mph is the biking speed
:
Find the walking speed using the 1st equation + =
multiply by 12w, results:
3w + 12 = 6w
12 = 6w - 3w
3w = 12
w = 4 mph is the walking speed
:
;
Check solution using the 1st equation + = + =
