Add 21/15 and 7/4
1st number: 1 6/15, 2nd number: 1 3/4
21/15 + 7/4 is 63/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 4 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 4 × 15 = 60,
7/4 = 7 × 15/4 × 15 = 105/60 - Add the two like fractions:
84/60 + 105/60 = 84 + 105/60 = 189/60 - 189/60 simplified gives 63/20
- So, 21/15 + 7/4 = 63/20
In mixed form: 33/20
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