Add 80/21 and 9/20
1st number: 3 17/21, 2nd number: 9/20
80/21 + 9/20 is 1789/420.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
80/21 = 80 × 20/21 × 20 = 1600/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
9/20 = 9 × 21/20 × 21 = 189/420 - Add the two like fractions:
1600/420 + 189/420 = 1600 + 189/420 = 1789/420 - So, 80/21 + 9/20 = 1789/420
In mixed form: 4109/420
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