Add 21/15 and 7/20
1st number: 1 6/15, 2nd number: 7/20
21/15 + 7/20 is 7/4.
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,
7/20 = 7 × 3/20 × 3 = 21/60 - Add the two like fractions:
84/60 + 21/60 = 84 + 21/60 = 105/60 - 105/60 simplified gives 7/4
- So, 21/15 + 7/20 = 7/4
In mixed form: 13/4
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