Add 3/7 and 21/40
3/7 + 21/40 is 267/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 7 × 40 = 280,
3/7 = 3 × 40/7 × 40 = 120/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Add the two like fractions:
120/280 + 147/280 = 120 + 147/280 = 267/280 - So, 3/7 + 21/40 = 267/280
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