Add 20/84 and 42/80
20/84 + 42/80 is 641/840.
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,
20/84 = 20 × 20/84 × 20 = 400/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
42/80 = 42 × 21/80 × 21 = 882/1680 - Add the two like fractions:
400/1680 + 882/1680 = 400 + 882/1680 = 1282/1680 - 1282/1680 simplified gives 641/840
- So, 20/84 + 42/80 = 641/840
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