Add 21/15 and 7/18
1st number: 1 6/15, 2nd number: 7/18
21/15 + 7/18 is 161/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 15 × 6 = 90,
21/15 = 21 × 6/15 × 6 = 126/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
7/18 = 7 × 5/18 × 5 = 35/90 - Add the two like fractions:
126/90 + 35/90 = 126 + 35/90 = 161/90 - So, 21/15 + 7/18 = 161/90
In mixed form: 171/90
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