Add 1/21 and 81/80
1st number: 1/21, 2nd number: 1 1/80
1/21 + 81/80 is 1781/1680.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
1/21 = 1 × 80/21 × 80 = 80/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
81/80 = 81 × 21/80 × 21 = 1701/1680 - Add the two like fractions:
80/1680 + 1701/1680 = 80 + 1701/1680 = 1781/1680 - So, 1/21 + 81/80 = 1781/1680
In mixed form: 1101/1680
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