Add 81/30 and 12/21
1st number: 2 21/30, 2nd number: 12/21
81/30 + 12/21 is 229/70.
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,
81/30 = 81 × 7/30 × 7 = 567/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
12/21 = 12 × 10/21 × 10 = 120/210 - Add the two like fractions:
567/210 + 120/210 = 567 + 120/210 = 687/210 - 687/210 simplified gives 229/70
- So, 81/30 + 12/21 = 229/70
In mixed form: 319/70
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