Respuesta :
let x be the factor that both the numerator and denominator are multiplied by to have an equivalent fraction.
so 6x/7x is 6/7
then
6x+7x=78
13x=78
x=78/13
x=6
therefore the fraction is (6*6)/(7*6) or 36/42
check: 36+42=78 !
so 6x/7x is 6/7
then
6x+7x=78
13x=78
x=78/13
x=6
therefore the fraction is (6*6)/(7*6) or 36/42
check: 36+42=78 !