Add 81/21 and 36/63
1st number: 3 18/21, 2nd number: 36/63
81/21 + 36/63 is 31/7.
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,
36/63 = 36 × 1/63 × 1 = 36/63 - Add the two like fractions:
243/63 + 36/63 = 243 + 36/63 = 279/63 - 279/63 simplified gives 31/7
- So, 81/21 + 36/63 = 31/7
In mixed form: 43/7
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