SCOREs OF 83,76, AND 79 ON test.AVERAGE OF AT LEAST 80 WHAT ARE THE POSSIBLE SCORES HE CAN MAKE ON HIS FOURTH TEST

Question

Robert Murphy has  FIRST THREE TESTS IN MATH 1031. 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 1

let x be the score needed on the 4th test:

(83+76+79+x)/4 >= 80

(238+x)/4 >= 80

238+x >= 320

x >= 82

 

Look to see if this makes sense.  He has two tests under 80, one he missed by 4 points and one by 1 point.  This means he needs to 'make up' 5 points to get to the average.  He had one test where he beat the average by 3 points meaning he had 2 left to make up, which goes along with the 82 he needs to score.