Add 21/18 and 90/21
1st number: 1 3/18, 2nd number: 4 6/21
21/18 + 90/21 is 229/42.
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,
90/21 = 90 × 6/21 × 6 = 540/126 - Add the two like fractions:
147/126 + 540/126 = 147 + 540/126 = 687/126 - 687/126 simplified gives 229/42
- So, 21/18 + 90/21 = 229/42
In mixed form: 519/42
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