Add 12/54 and 20/21
12/54 + 20/21 is 74/63.
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,
12/54 = 12 × 7/54 × 7 = 84/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
20/21 = 20 × 18/21 × 18 = 360/378 - Add the two like fractions:
84/378 + 360/378 = 84 + 360/378 = 444/378 - 444/378 simplified gives 74/63
- So, 12/54 + 20/21 = 74/63
In mixed form: 111/63
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