Add 42/18 and 72/21
1st number: 2 6/18, 2nd number: 3 9/21
42/18 + 72/21 is 121/21.
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,
42/18 = 42 × 7/18 × 7 = 294/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
72/21 = 72 × 6/21 × 6 = 432/126 - Add the two like fractions:
294/126 + 432/126 = 294 + 432/126 = 726/126 - 726/126 simplified gives 121/21
- So, 42/18 + 72/21 = 121/21
In mixed form: 516/21
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