Add 21/15 and 81/20
1st number: 1 6/15, 2nd number: 4 1/20
21/15 + 81/20 is 109/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 20 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 15 × 4 = 60,
21/15 = 21 × 4/15 × 4 = 84/60 - Likewise, for the 2nd fraction, since 20 × 3 = 60,
81/20 = 81 × 3/20 × 3 = 243/60 - Add the two like fractions:
84/60 + 243/60 = 84 + 243/60 = 327/60 - 327/60 simplified gives 109/20
- So, 21/15 + 81/20 = 109/20
In mixed form: 59/20
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