Add 70/18 and 9/21
1st number: 3 16/18, 2nd number: 9/21
70/18 + 9/21 is 272/63.
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,
9/21 = 9 × 6/21 × 6 = 54/126 - Add the two like fractions:
490/126 + 54/126 = 490 + 54/126 = 544/126 - 544/126 simplified gives 272/63
- So, 70/18 + 9/21 = 272/63
In mixed form: 420/63
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