A ranch hand herded his cattle to some grazing land. Then he began riding back to the ranch, which is due west, at 7 kilometers
per hour. Simultaneously, the cows began moving away from him, too, headed due east at 2 kilometers per hour. How long did it take for the herd and the ranch hand to be 4 kilometers apart?
Let d be distance travelled when they are level , and t = time that nora took to get level with mason
for Nora
6 = d/t
d = 6t
for Mason
5 = d / (t + 35)
d = 5 ( t + 350
so 6t = 5(t + 35)
solve for t
