Add 81/42 and 20/30
1st number: 1 39/42, 2nd number: 20/30
81/42 + 20/30 is 109/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
81/42 = 81 × 5/42 × 5 = 405/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
20/30 = 20 × 7/30 × 7 = 140/210 - Add the two like fractions:
405/210 + 140/210 = 405 + 140/210 = 545/210 - 545/210 simplified gives 109/42
- So, 81/42 + 20/30 = 109/42
In mixed form: 225/42
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