Add 21/12 and 90/28
1st number: 1 9/12, 2nd number: 3 6/28
21/12 + 90/28 is 139/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
21/12 = 21 × 7/12 × 7 = 147/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
90/28 = 90 × 3/28 × 3 = 270/84 - Add the two like fractions:
147/84 + 270/84 = 147 + 270/84 = 417/84 - 417/84 simplified gives 139/28
- So, 21/12 + 90/28 = 139/28
In mixed form: 427/28
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