### Home > CC2 > Chapter 7 > Lesson 7.2.2 > Problem7-115

7-115.

For each equation below, solve for $x$. Sometimes the easiest strategy is to use mental math.  Homework Help ✎

1. $x - \frac { 3 } { 5 } = 1 \frac { 2 } { 5 }$

What does $\frac{3}{5}+\frac{2}{5}=?$

1. $5.2 + x = 10.95$

$x=5.75$

1. $2x-3.25=7.15$

$x=5.2$
Be sure to know how to get this answer using mental math. Recognize that $3.25+7.15$ equals an even decimal, $10.4$.

1. $\frac { x } { 16 } = \frac { 3 } { 8 }$

$8(2)=16$
What must $x$ be?