Ok, here's how you would find the answer. First, you need to give both fractions a like denominator. 1/7 1/5 35 would be the lowest number that both fractions can have. So.... To change 1/7 (which is in simplest form, of course) to a fraction with a denominator of 35 (which would be a fraction not in simplest form) you multiply.. 7x?=35 7x5=35 (35 is automatically the denominator) 1x? 1x5=5(numerator)(Multiply both by 5 because that's what 7 is multiplied by to get 35) So 1/7 now =5/35 Now we do the same thing for 1/5, only we do it according to this fraction. 5x?=35 5x7=35 SO 1x7=7(numerator) 1/5 now =7/35 So we have 1/7=5/35 and 1/5=7/35 Now when adding fractions with like denominators(35 and 35), you don't add the denominators. Just add 7+5 ( 7/35 5/35 ). So it's now 12/35. Since this cannot be reduced, your answer to 1/7 + 1/5 = 12/35 Hope that helped you.