Add 20/21 and 72/18
1st number: 20/21, 2nd number: 4 0/18
20/21 + 72/18 is 104/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
20/21 = 20 × 6/21 × 6 = 120/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
72/18 = 72 × 7/18 × 7 = 504/126 - Add the two like fractions:
120/126 + 504/126 = 120 + 504/126 = 624/126 - 624/126 simplified gives 104/21
- So, 20/21 + 72/18 = 104/21
In mixed form: 420/21
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