Add 4/81 and 21/20
1st number: 4/81, 2nd number: 1 1/20
4/81 + 21/20 is 1781/1620.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 20 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 81 × 20 = 1620,
4/81 = 4 × 20/81 × 20 = 80/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
21/20 = 21 × 81/20 × 81 = 1701/1620 - Add the two like fractions:
80/1620 + 1701/1620 = 80 + 1701/1620 = 1781/1620 - So, 4/81 + 21/20 = 1781/1620
In mixed form: 1161/1620
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