Add 42/80 and 21/84
42/80 + 21/84 is 31/40.
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,
42/80 = 42 × 21/80 × 21 = 882/1680 - Likewise, for the 2nd fraction, since 84 × 20 = 1680,
21/84 = 21 × 20/84 × 20 = 420/1680 - Add the two like fractions:
882/1680 + 420/1680 = 882 + 420/1680 = 1302/1680 - 1302/1680 simplified gives 31/40
- So, 42/80 + 21/84 = 31/40
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