Evaluate -1/8-2/7

$- \frac{1}{8} - \frac{2}{7}$

Step 1

To write $- \frac{1}{8}$ as a fraction with a common denominator, multiply by $\frac{7}{7}$ .

$- \frac{1}{8} \cdot \frac{7}{7} - \frac{2}{7}$

Step 2

To write $- \frac{2}{7}$ as a fraction with a common denominator, multiply by $\frac{8}{8}$ .

$- \frac{1}{8} \cdot \frac{7}{7} - \frac{2}{7} \cdot \frac{8}{8}$

Step 3

Write each expression with a common denominator of $56$ , by multiplying each by an appropriate factor of $1$ .

Multiply $\frac{1}{8}$ by $\frac{7}{7}$ .

$- \frac{7}{8 \cdot 7} - \frac{2}{7} \cdot \frac{8}{8}$

Multiply $8$ by $7$ .

$- \frac{7}{56} - \frac{2}{7} \cdot \frac{8}{8}$

Multiply $\frac{2}{7}$ by $\frac{8}{8}$ .

$- \frac{7}{56} - \frac{2 \cdot 8}{7 \cdot 8}$

Multiply $7$ by $8$ .

$- \frac{7}{56} - \frac{2 \cdot 8}{56}$

Step 4

Combine the numerators over the common denominator.

$\frac{- 7 - 2 \cdot 8}{56}$

Step 5

Simplify the numerator.

Multiply $- 2$ by $8$ .

$\frac{- 7 - 16}{56}$

Subtract $16$ from $- 7$ .

$\frac{- 23}{56}$

Step 6

Move the negative in front of the fraction.

$- \frac{23}{56}$

Step 7

The result can be shown in multiple forms.

Exact Form:

$- \frac{23}{56}$

Decimal Form:

$- 0.41071428 \dots$