Question

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

A.) 7/15

B.) 19/42

C.) 15/42

D.) 4/9

Answer 1

B) 19/42

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

`(10)/(21) - (3)/(7) = (10)/(21) - (9)/(21) = (1)/(21)`

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

`(3)/(7) + (1)/(42) = (18)/(42) + (1)/(42) = (19)/(42)`