The pair of fraction that has the same denominator of 42 are 3 2/3 and 5/7.
First fraction 3 2/3 = 11/3
Second fraction = 5/7
If we look at the denominator of both fractions i.e 3 and 7, they are both factor of 42. Since this two values can easily go in 42 without remainder, then we can conclude that both fraction initially has a denominator of 42.
