How do you evaluate 4 2/7 - 1/6?

Jul 16, 2016

You can convert the numbers to fractions and add them up

Explanation:

$4 \frac{2}{7} = 4 + \frac{2}{7} = \frac{28}{7} + \frac{2}{7}$, since $4 = \frac{28}{7}$

Observe that we have chosen the denominator $7$ carefully, because now we have:

$4 + \frac{2}{7} = \frac{28}{7} + \frac{2}{7} = \frac{30}{7}$. And now we can subtract:

$\frac{30}{7} - \frac{1}{6} = \frac{180}{42} - \frac{7}{42}$ where again we have chosen $42$ as the denominator because both $7$ and $6$ divide $42$. Now we then have:

$\frac{30}{7} - \frac{1}{6} = \frac{180}{42} - \frac{7}{42} = \frac{173}{42}$, or if you prefer $4 \frac{5}{42}$, both are correct answers