Add 81/21 and 90/63
1st number: 3 18/21, 2nd number: 1 27/63
81/21 + 90/63 is 37/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
81/21 = 81 × 3/21 × 3 = 243/63 - Likewise, for the 2nd fraction, since 63 × 1 = 63,
90/63 = 90 × 1/63 × 1 = 90/63 - Add the two like fractions:
243/63 + 90/63 = 243 + 90/63 = 333/63 - 333/63 simplified gives 37/7
- So, 81/21 + 90/63 = 37/7
In mixed form: 52/7
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