Add 20/54 and 40/21
1st number: 20/54, 2nd number: 1 19/21
20/54 + 40/21 is 430/189.
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,
40/21 = 40 × 18/21 × 18 = 720/378 - Add the two like fractions:
140/378 + 720/378 = 140 + 720/378 = 860/378 - 860/378 simplified gives 430/189
- So, 20/54 + 40/21 = 430/189
In mixed form: 252/189
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