Add 21/80 and 12/42
21/80 + 12/42 is 307/560.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 42 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 42 × 40 = 1680,
12/42 = 12 × 40/42 × 40 = 480/1680 - Add the two like fractions:
441/1680 + 480/1680 = 441 + 480/1680 = 921/1680 - 921/1680 simplified gives 307/560
- So, 21/80 + 12/42 = 307/560
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