Add 21/40 and 7/28
21/40 + 7/28 is 31/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 28 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Likewise, for the 2nd fraction, since 28 × 10 = 280,
7/28 = 7 × 10/28 × 10 = 70/280 - Add the two like fractions:
147/280 + 70/280 = 147 + 70/280 = 217/280 - 217/280 simplified gives 31/40
- So, 21/40 + 7/28 = 31/40
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