Question 1044744
mean=total/number
88=total/4
352=total
the three scores known are 84,87, and 91=262.
subtract from the new total, and 352-262=90
Check
test one is 4 below the mean, test 2 is 1 below, test 3 is 3 above, and to balance, test 4 must be 2 above. That would require it to be 90.