Add 21/28 and 27/40
21/28 + 27/40 is 57/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 28 × 10 = 280,
21/28 = 21 × 10/28 × 10 = 210/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
27/40 = 27 × 7/40 × 7 = 189/280 - Add the two like fractions:
210/280 + 189/280 = 210 + 189/280 = 399/280 - 399/280 simplified gives 57/40
- So, 21/28 + 27/40 = 57/40
In mixed form: 117/40
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