Add 21/56 and 20/40
21/56 + 20/40 is 7/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 56 × 5 = 280,
21/56 = 21 × 5/56 × 5 = 105/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
20/40 = 20 × 7/40 × 7 = 140/280 - Add the two like fractions:
105/280 + 140/280 = 105 + 140/280 = 245/280 - 245/280 simplified gives 7/8
- So, 21/56 + 20/40 = 7/8
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