Which fraction is halfway between 3/7 and 10/21

Mathematics

1 answer:

Aleks [24]3 years ago

6 0

Answer:

B) 19/42

Step-by-step explanation:

To find the fraction halfway between 3/7 and 10/21 we first find the difference between the fractions, half it, and then add it back on to the smaller one.

Because 10/21 > 3/7 we subtract in that order

$\frac{10}{21} - \frac{3}{7} = \frac{10}{21} - \frac{9}{21} = \frac{1}{21}$

Half of 1/21 is 1/42 and so the fraction halfway between 3/7 and 10/21 is

$\frac{3}{7} + \frac{1}{42} = \frac{18}{42} + \frac{1}{42} = \frac{19}{42}$

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