Add 3/42 and 81/20
1st number: 3/42, 2nd number: 4 1/20
3/42 + 81/20 is 577/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
3/42 = 3 × 10/42 × 10 = 30/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
81/20 = 81 × 21/20 × 21 = 1701/420 - Add the two like fractions:
30/420 + 1701/420 = 30 + 1701/420 = 1731/420 - 1731/420 simplified gives 577/140
- So, 3/42 + 81/20 = 577/140
In mixed form: 417/140
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