Add 21/15 and 18/20
1st number: 1 6/15, 2nd number: 18/20
21/15 + 18/20 is 23/10.
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,
18/20 = 18 × 3/20 × 3 = 54/60 - Add the two like fractions:
84/60 + 54/60 = 84 + 54/60 = 138/60 - 138/60 simplified gives 23/10
- So, 21/15 + 18/20 = 23/10
In mixed form: 23/10
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