Question

30/7 - 19/3 + 8/21 ygyhfuftufgyugyhyigyighygiigiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii

Answer 1

-
`(35)/(21)`

Explanation:

`(30)/(7)` -
`(19)/(3)` +
`(8)/(21)`

we require the 3 fractions to have a common denominator

the lowest common denominator of 7, 3 and 21 is 21

multiply the numerator / denominator of the first fraction by 3

multiply the numerator/denominator of the second fraction by 7

=
`(30(3))/(7(3))` -
`(19(7))/(3(7))` +
`(8)/(21)`

=
`(90)/(21)` -
`(133)/(21)` +
`(8)/(21)`

now combine the values on the numerator, over common denominator 21

=
`(90-133+8)/(21)`

=
`(-35)/(21)`

= -
`(35)/(21)`