Question 253210
In a unit of time T
T(180 +w) = 7 and T(180 - w) = 5
so 7/(180 +w) = 5/(180 - w
rearranging 5 x(180 + w) = 7 x(180 - w)
900 + 5x = 1260 - 7w
12w = 360
w = 30