Question

What is Andrea's rate in mi/h?
Andrea can ride her bike 2 mi/h faster than Ruby. It takes Andrea 48 min less to travel 50 mi than it does Ruby. What is Andrea's rate in mi/h?

explain steps :D

Answer 1

let x = Ruby's speed, y = Ruby's time

Ruby:

d = rt

50 = x*y

y = 50/x

Andrea:

d = rt

50 = (x+2)*(y-48)

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Now plug in y = 50/x into the last equation above and solve for x