Add 21/30 and 20/21
21/30 + 20/21 is 347/210.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
20/21 = 20 × 10/21 × 10 = 200/210 - Add the two like fractions:
147/210 + 200/210 = 147 + 200/210 = 347/210 - So, 21/30 + 20/21 = 347/210
In mixed form: 1137/210
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