(72+67+82+79+f)/5 >=80 to find the average we add up all the scores and divide by the number. she took 4 tests plus the final which is 5. It must be greater than or equal to 80
(300+f)/5>=80 added up the test scores
300+f >= 400 multiply each side by 5
f>= 100 subtract 100 from each side
Trinda needs 100 or greater
