## Algebra 1: Common Core (15th Edition)

The mean is 91 and the values are:9 9, 86, 76 and 95.You have to find the fifth value. Using the mean formula, you find x: $\frac{99+ 86+ 76+ 95+ x}{5}$=91 -Multiply both sides by 5 to isolate x- 99+86+76+95+x=455 -simplify- 356+x=455 -subtract 356 from both sides to solve for x- x=99 Check your work: $\frac{99+ 86+ 76+ 95+ 99}{5}$=$\frac{455}{5}$=99. So the missing value is 99.