Add 21/40 and 12/7
1st number: 21/40, 2nd number: 1 5/7
21/40 + 12/7 is 627/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 7 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 7 × 40 = 280,
12/7 = 12 × 40/7 × 40 = 480/280 - Add the two like fractions:
147/280 + 480/280 = 147 + 480/280 = 627/280 - So, 21/40 + 12/7 = 627/280
In mixed form: 267/280
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