Convert the fraction to high terms. enter the value of the missing numerator: 5/13 = ? /78

So,

The easy way to do this is to recognize that 13 is a factor of 78.  Once we recognize that 13 * 6 = 78, we can simply multiply the numerator by 6 to get the missing numerator.

5 * 6 = 30

The missing numerator is 30.