Add 81/4 and 36/21
1st number: 20 1/4, 2nd number: 1 15/21
81/4 + 36/21 is 615/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
81/4 = 81 × 21/4 × 21 = 1701/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
36/21 = 36 × 4/21 × 4 = 144/84 - Add the two like fractions:
1701/84 + 144/84 = 1701 + 144/84 = 1845/84 - 1845/84 simplified gives 615/28
- So, 81/4 + 36/21 = 615/28
In mixed form: 2127/28
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