Add 21/28 and 28/40
21/28 + 28/40 is 29/20.
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,
28/40 = 28 × 7/40 × 7 = 196/280 - Add the two like fractions:
210/280 + 196/280 = 210 + 196/280 = 406/280 - 406/280 simplified gives 29/20
- So, 21/28 + 28/40 = 29/20
In mixed form: 19/20
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