Add 81/21 and 56/28
1st number: 3 18/21, 2nd number: 2 0/28
81/21 + 56/28 is 41/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
81/21 = 81 × 4/21 × 4 = 324/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
56/28 = 56 × 3/28 × 3 = 168/84 - Add the two like fractions:
324/84 + 168/84 = 324 + 168/84 = 492/84 - 492/84 simplified gives 41/7
- So, 81/21 + 56/28 = 41/7
In mixed form: 56/7
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