Add 21/28 and 28/81
21/28 + 28/81 is 355/324.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 81 is 2268
Next, find the equivalent fraction of both fractional numbers with denominator 2268 - For the 1st fraction, since 28 × 81 = 2268,
21/28 = 21 × 81/28 × 81 = 1701/2268 - Likewise, for the 2nd fraction, since 81 × 28 = 2268,
28/81 = 28 × 28/81 × 28 = 784/2268 - Add the two like fractions:
1701/2268 + 784/2268 = 1701 + 784/2268 = 2485/2268 - 2485/2268 simplified gives 355/324
- So, 21/28 + 28/81 = 355/324
In mixed form: 131/324
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