Add 80/21 and 56/40
1st number: 3 17/21, 2nd number: 1 16/40
80/21 + 56/40 is 547/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
80/21 = 80 × 40/21 × 40 = 3200/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
56/40 = 56 × 21/40 × 21 = 1176/840 - Add the two like fractions:
3200/840 + 1176/840 = 3200 + 1176/840 = 4376/840 - 4376/840 simplified gives 547/105
- So, 80/21 + 56/40 = 547/105
In mixed form: 522/105
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