Add 21/18 and 15/21
1st number: 1 3/18, 2nd number: 15/21
21/18 + 15/21 is 79/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
15/21 = 15 × 6/21 × 6 = 90/126 - Add the two like fractions:
147/126 + 90/126 = 147 + 90/126 = 237/126 - 237/126 simplified gives 79/42
- So, 21/18 + 15/21 = 79/42
In mixed form: 137/42
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