A boat travelled upstream a distance of 90 miles at a average speed of
(v-3) miles per hour and then travelled the same distance downstream at
a average speed of (v+3) miles per hour.If the trip upstream took half an hour longer than the trip downstream. How many hours it take the boat to
travel downstream?

A) 2.5

B) 2.4

C) 2.3

D) 2.2

E) 2.1

[spoiler]A
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