Add 81/30 and 20/28
1st number: 2 21/30, 2nd number: 20/28
81/30 + 20/28 is 239/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 28 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 30 × 14 = 420,
81/30 = 81 × 14/30 × 14 = 1134/420 - Likewise, for the 2nd fraction, since 28 × 15 = 420,
20/28 = 20 × 15/28 × 15 = 300/420 - Add the two like fractions:
1134/420 + 300/420 = 1134 + 300/420 = 1434/420 - 1434/420 simplified gives 239/70
- So, 81/30 + 20/28 = 239/70
In mixed form: 329/70
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