Add 21/80 and 8/21
21/80 + 8/21 is 1081/1680.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
21/80 = 21 × 21/80 × 21 = 441/1680 - Likewise, for the 2nd fraction, since 21 × 80 = 1680,
8/21 = 8 × 80/21 × 80 = 640/1680 - Add the two like fractions:
441/1680 + 640/1680 = 441 + 640/1680 = 1081/1680 - So, 21/80 + 8/21 = 1081/1680
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