Add 42/84 and 21/80
42/84 + 21/80 is 61/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 84 × 20 = 1680,
42/84 = 42 × 20/84 × 20 = 840/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
21/80 = 21 × 21/80 × 21 = 441/1680 - Add the two like fractions:
840/1680 + 441/1680 = 840 + 441/1680 = 1281/1680 - 1281/1680 simplified gives 61/80
- So, 42/84 + 21/80 = 61/80
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