Add 21/80 and 63/84
21/80 + 63/84 is 81/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 84 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 84 × 20 = 1680,
63/84 = 63 × 20/84 × 20 = 1260/1680 - Add the two like fractions:
441/1680 + 1260/1680 = 441 + 1260/1680 = 1701/1680 - 1701/1680 simplified gives 81/80
- So, 21/80 + 63/84 = 81/80
In mixed form: 11/80
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