Posted by david on .
Caleb scored the following on his first four tests: 78, 84, 88, and 82. What is the least grade he can receive on his next test to have an average of 85 for the five tests?
a.66
b.83
c.93
d.100

9gr 
bobpursley,
5*85=78+84+88+82+N
solve for N 
9gr 
ruslan,
83

9gr 
ruslan,
93