Problema Solution
brent has grades of 86,88 and 78 on his first on his three test on college algebra. If he wants an average of at least 80 after his fourth test, what are the possible scores he can make on his fourth test.
Answer provided by our tutors
Let x be the score of this last forth test.
The average of his 4 tests is (86+88+78+x)/4 and has to be at least 80 that is
(86+88+78+x)/4 >=80
x >= 68
On his forth test Brent has to have score of 68 or more.