Solve for b 3/10=(b+7)/20

$\frac{3}{10} = \frac{b + 7}{20}$

Step 1

Rewrite the equation as $\frac{b + 7}{20} = \frac{3}{10}$ .

$\frac{b + 7}{20} = \frac{3}{10}$

Step 2

Multiply both sides of the equation by $20$ .

$20 \frac{b + 7}{20} = 20 (\frac{3}{10})$

Step 3

Simplify both sides of the equation.

Simplify the left side.

Cancel the common factor of $20$ .

Cancel the common factor.

$20 \frac{b + 7}{20} = 20 (\frac{3}{10})$

Rewrite the expression.

$b + 7 = 20 (\frac{3}{10})$

Simplify the right side.

Simplify $20 (\frac{3}{10})$ .

Cancel the common factor of $10$ .

Factor $10$ out of $20$ .

$b + 7 = 10 (2) \frac{3}{10}$

Cancel the common factor.

$b + 7 = 10 \cdot 2 \frac{3}{10}$

Rewrite the expression.

$b + 7 = 2 \cdot 3$

Multiply $2$ by $3$ .

$b + 7 = 6$

Step 4

Move all terms not containing $b$ to the right side of the equation.

Subtract $7$ from both sides of the equation.

$b = 6 - 7$

Subtract $7$ from $6$ .

$b = - 1$