Add 20/12 and 45/42
1st number: 1 8/12, 2nd number: 1 3/42
20/12 + 45/42 is 115/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
20/12 = 20 × 7/12 × 7 = 140/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
45/42 = 45 × 2/42 × 2 = 90/84 - Add the two like fractions:
140/84 + 90/84 = 140 + 90/84 = 230/84 - 230/84 simplified gives 115/42
- So, 20/12 + 45/42 = 115/42
In mixed form: 231/42
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