Add 72/18 and 2/21
1st number: 4 0/18, 2nd number: 2/21
72/18 + 2/21 is 86/21.
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,
72/18 = 72 × 7/18 × 7 = 504/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
2/21 = 2 × 6/21 × 6 = 12/126 - Add the two like fractions:
504/126 + 12/126 = 504 + 12/126 = 516/126 - 516/126 simplified gives 86/21
- So, 72/18 + 2/21 = 86/21
In mixed form: 42/21
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