Add 21/80 and 75/84
21/80 + 75/84 is 647/560.
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,
75/84 = 75 × 20/84 × 20 = 1500/1680 - Add the two like fractions:
441/1680 + 1500/1680 = 441 + 1500/1680 = 1941/1680 - 1941/1680 simplified gives 647/560
- So, 21/80 + 75/84 = 647/560
In mixed form: 187/560
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