Add 80/21 and 56/20
1st number: 3 17/21, 2nd number: 2 16/20
80/21 + 56/20 is 694/105.
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,
56/20 = 56 × 21/20 × 21 = 1176/420 - Add the two like fractions:
1600/420 + 1176/420 = 1600 + 1176/420 = 2776/420 - 2776/420 simplified gives 694/105
- So, 80/21 + 56/20 = 694/105
In mixed form: 664/105
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