Add 81/21 and 5/4
1st number: 3 18/21, 2nd number: 1 1/4
81/21 + 5/4 is 143/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 4 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 4 × 21 = 84,
5/4 = 5 × 21/4 × 21 = 105/84 - Add the two like fractions:
324/84 + 105/84 = 324 + 105/84 = 429/84 - 429/84 simplified gives 143/28
- So, 81/21 + 5/4 = 143/28
In mixed form: 53/28
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