Question

A student has gotten the following grades on his tests: 87, 95, 86, and 88. He needs to have an average of 90 to receive an A for the class. What is the minimum grade he must get on the last test in order to have an average of 90?
(Measures of Central Tendency and Dispersion)

Answer 1

The student needs an average of 90 and he has the following grades :
87,95,86,88
in order to get a 90 average he has to get
 90x5=450
87+95+86+88+?=450,  356+?=450 , 450-356=94
the answer is 94