Algebra
posted by Robert on .
Algebra Question: A team wins 15 of their first 20 games. If they win only half the time from now on, how many games will they have to play in order to win 60% of their total games? I have it figured out manually, but cant get it in equation form.

total number of games  x
played so far  20
to be played  x20
(15 + (x20)/2 )/x = 6/10
15 + x/2  10 = (6/10)x
times 10
150 + 5x  100 = 6x
x = 50
So they still have to play 30 games and win 15 of those.
check:
Having won 15 so far, and still hoping to win 15 more, ....
30/50 = 6/10 = 60%