Add 21/40 and 18/28
21/40 + 18/28 is 327/280.
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,
18/28 = 18 × 10/28 × 10 = 180/280 - Add the two like fractions:
147/280 + 180/280 = 147 + 180/280 = 327/280 - So, 21/40 + 18/28 = 327/280
In mixed form: 147/280
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