Problema Solution
Red Riding Hood drives the 432 miles to Grandmother’s house in 1 hour less than it takes the Wolf to drive the same route. Her average speed is 6 mph faster than the Wolf’s average speed. How fast does Red Riding Hood drive?
Answer provided by our tutors
let
d = 432 mi the distance
v + 6 = the rate of Red Riding Hood
v = the rate of the wolf, v>0
t = the time of the Red Riding Hood
t + 1 = the time of the Wolf
since distance = rate*time we have
(v+6)*t = 432 => t = 432/(v+6)
v(t+1) = 432
plug t = 432/(v+6) into the last equation
v(432/(v+6) + 1) = 432
by solving we find
v = 48 mph
click here to see the step by step solution of the equation
48 + 6 = 54
the rate of Red Riding Hood is 54 mph.