Add 21/10 and 28/21
1st number: 2 1/10, 2nd number: 1 7/21
21/10 + 28/21 is 103/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
21/10 = 21 × 21/10 × 21 = 441/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
28/21 = 28 × 10/21 × 10 = 280/210 - Add the two like fractions:
441/210 + 280/210 = 441 + 280/210 = 721/210 - 721/210 simplified gives 103/30
- So, 21/10 + 28/21 = 103/30
In mixed form: 313/30
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