Add 20/12 and 5/21
1st number: 1 8/12, 2nd number: 5/21
20/12 + 5/21 is 40/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 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 21 × 4 = 84,
5/21 = 5 × 4/21 × 4 = 20/84 - Add the two like fractions:
140/84 + 20/84 = 140 + 20/84 = 160/84 - 160/84 simplified gives 40/21
- So, 20/12 + 5/21 = 40/21
In mixed form: 119/21
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