If ur doing addition with unequal denominator then u from the LCM for the two unlike denominators for example I have 2/3 + 1/5 the common multiple for 5 and 3 is 15 so to 2/3 I do 2(numerator)*5 and 3(denominator)*5, what u do to the bottom u do to the top and then the other 1(numerator)*3 and 5(denominator)*3, so ur new fractions are 10/15 + 3/15= 13/15 HOPE THIS HELPS, ALSO THE ANSWER S 13/15
