Question

Chloe has taken four tests this semester. Her scores on the three tests are 87, 78, and 61. If her test average is 78.5, what is her grade on her 4th test?

Answer 1

n = last test

(87 + 78 + 61 + n) : 4 = 78,5

87 + 78 + 61 + n   = 78,5 x 4

n = 314 - 226

n = 88