Add 90/12 and 63/21
1st number: 7 6/12, 2nd number: 3 0/21
90/12 + 63/21 is 21/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
90/12 = 90 × 7/12 × 7 = 630/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
63/21 = 63 × 4/21 × 4 = 252/84 - Add the two like fractions:
630/84 + 252/84 = 630 + 252/84 = 882/84 - 882/84 simplified gives 21/2
- So, 90/12 + 63/21 = 21/2
In mixed form: 101/2
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