Add 81/63 and 3/21
1st number: 1 18/63, 2nd number: 3/21
81/63 + 3/21 is 10/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 63 × 1 = 63,
81/63 = 81 × 1/63 × 1 = 81/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
3/21 = 3 × 3/21 × 3 = 9/63 - Add the two like fractions:
81/63 + 9/63 = 81 + 9/63 = 90/63 - 90/63 simplified gives 10/7
- So, 81/63 + 3/21 = 10/7
In mixed form: 13/7
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