Whitney left school and drove 7 miles to meet her mother at a restaurant. Her mother left at the same time and drove 8 miles, traveling 5 mi/h faster than her daughter. If the two arrived at the restaurant at the same time, what was Whitney’s speed?

Question

anonymous · Answer

@johnweldon1993

zpupster · Answer

w = the speed of Whitney

m = the speed of her mother

m = w + 5

7/w = 8/m cross multiply

7m = 8w

zpupster · Answer

plug m = w + 5 into the last equation

7(w + 5) = 8w

anonymous · Answer

ok

zpupster · Answer

7w+35 = 8w

7w-7w+35 =8w-7w
w=35