Add 72/18 and 84/21
1st number: 4 0/18, 2nd number: 4 0/21
72/18 + 84/21 is 8/1.
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,
84/21 = 84 × 6/21 × 6 = 504/126 - Add the two like fractions:
504/126 + 504/126 = 504 + 504/126 = 1008/126 - 1008/126 simplified gives 8/1
- So, 72/18 + 84/21 = 8/1
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