Add 70/18 and 90/21
1st number: 3 16/18, 2nd number: 4 6/21
70/18 + 90/21 is 515/63.
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,
70/18 = 70 × 7/18 × 7 = 490/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
90/21 = 90 × 6/21 × 6 = 540/126 - Add the two like fractions:
490/126 + 540/126 = 490 + 540/126 = 1030/126 - 1030/126 simplified gives 515/63
- So, 70/18 + 90/21 = 515/63
In mixed form: 811/63
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