Evaluate 1/7-1/8

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

Step 1

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

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

Step 2

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

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

Step 3

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

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

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

Multiply $7$ by $8$ .

$\frac{8}{56} - \frac{1}{8} \cdot \frac{7}{7}$

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

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

Multiply $8$ by $7$ .

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

Step 4

Combine the numerators over the common denominator.

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

Step 5

Subtract $7$ from $8$ .

$\frac{1}{56}$

Step 6

The result can be shown in multiple forms.

Exact Form:

$\frac{1}{56}$

Decimal Form:

$0.01785714 \dots$