Add 15/21 and 90/12
1st number: 15/21, 2nd number: 7 6/12
15/21 + 90/12 is 115/14.
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,
15/21 = 15 × 4/21 × 4 = 60/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
90/12 = 90 × 7/12 × 7 = 630/84 - Add the two like fractions:
60/84 + 630/84 = 60 + 630/84 = 690/84 - 690/84 simplified gives 115/14
- So, 15/21 + 90/12 = 115/14
In mixed form: 83/14
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