Add 21/84 and 90/12
1st number: 21/84, 2nd number: 7 6/12
21/84 + 90/12 is 31/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
21/84 = 21 × 1/84 × 1 = 21/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
90/12 = 90 × 7/12 × 7 = 630/84 - Add the two like fractions:
21/84 + 630/84 = 21 + 630/84 = 651/84 - 651/84 simplified gives 31/4
- So, 21/84 + 90/12 = 31/4
In mixed form: 73/4
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