Add 20/54 and 80/21
1st number: 20/54, 2nd number: 3 17/21
20/54 + 80/21 is 790/189.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
20/54 = 20 × 7/54 × 7 = 140/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
80/21 = 80 × 18/21 × 18 = 1440/378 - Add the two like fractions:
140/378 + 1440/378 = 140 + 1440/378 = 1580/378 - 1580/378 simplified gives 790/189
- So, 20/54 + 80/21 = 790/189
In mixed form: 434/189
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