Question 22 mary has scored 79 , 91 , 64 , 65 , and 71 on her previous five tests. what score does she need on her next test so that her average (mean is 77 ?
So u want to add all of the previous scores together and divide them by the number of scores [i.e: 79+91+64+65+71= 370 then u divide. 370/5 (since there are 5 sets of scores) which gets you 74.] Then it's kind of a guess and check from there. Answer: 92
