Solve the equation by finding the common multiple. three fourths minus two fifths plus eight twentieths equals blank

seven twentieths
fifteen twentieths
twenty fifteenths
thirteen twentieths

The answer is b.
15/20. multiply 3/4 by 5 on both the top and bottom,, the result is 15/20. Once you have 15/20 you take the other fraction (2/5) and multiply both the top and bottom by 4. You should end up with 8/20 now that both fractions have the same denominator you can subtract them. Once you do so the denominator will stay the same except the numerator you end up with 7/20 with this fraction you can add 8/20 when they are added together you should get 15/20.

The answer is b I hope that helped and btw have a good day