Question 387125
16=2(r+c)
16=8(r-c)



16=2r+2c
16=8r-8c



64=8r+8c
16=8r-8c


80=16r


r=5

16=2r+2c
16=2*5+2c
16=10+2c
6=2c

c=3


Answer: 3 mph