Add 12/28 and 81/30
1st number: 12/28, 2nd number: 2 21/30
12/28 + 81/30 is 219/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 30 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 28 × 15 = 420,
12/28 = 12 × 15/28 × 15 = 180/420 - Likewise, for the 2nd fraction, since 30 × 14 = 420,
81/30 = 81 × 14/30 × 14 = 1134/420 - Add the two like fractions:
180/420 + 1134/420 = 180 + 1134/420 = 1314/420 - 1314/420 simplified gives 219/70
- So, 12/28 + 81/30 = 219/70
In mixed form: 39/70
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