Add 90/21 and 81/12
1st number: 4 6/21, 2nd number: 6 9/12
90/21 + 81/12 is 309/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
90/21 = 90 × 4/21 × 4 = 360/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
81/12 = 81 × 7/12 × 7 = 567/84 - Add the two like fractions:
360/84 + 567/84 = 360 + 567/84 = 927/84 - 927/84 simplified gives 309/28
- So, 90/21 + 81/12 = 309/28
In mixed form: 111/28
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