Add 21/28 and 90/12
1st number: 21/28, 2nd number: 7 6/12
21/28 + 90/12 is 33/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
21/28 = 21 × 3/28 × 3 = 63/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
90/12 = 90 × 7/12 × 7 = 630/84 - Add the two like fractions:
63/84 + 630/84 = 63 + 630/84 = 693/84 - 693/84 simplified gives 33/4
- So, 21/28 + 90/12 = 33/4
In mixed form: 81/4
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