Add 72/18 and 90/21
1st number: 4 0/18, 2nd number: 4 6/21
72/18 + 90/21 is 58/7.
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,
90/21 = 90 × 6/21 × 6 = 540/126 - Add the two like fractions:
504/126 + 540/126 = 504 + 540/126 = 1044/126 - 1044/126 simplified gives 58/7
- So, 72/18 + 90/21 = 58/7
In mixed form: 82/7
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