Add 42/80 and 9/21
42/80 + 9/21 is 267/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 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 21 × 80 = 1680,
9/21 = 9 × 80/21 × 80 = 720/1680 - Add the two like fractions:
882/1680 + 720/1680 = 882 + 720/1680 = 1602/1680 - 1602/1680 simplified gives 267/280
- So, 42/80 + 9/21 = 267/280
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