Add 20/21 and 42/54
20/21 + 42/54 is 109/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 21 × 18 = 378,
20/21 = 20 × 18/21 × 18 = 360/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
42/54 = 42 × 7/54 × 7 = 294/378 - Add the two like fractions:
360/378 + 294/378 = 360 + 294/378 = 654/378 - 654/378 simplified gives 109/63
- So, 20/21 + 42/54 = 109/63
In mixed form: 146/63
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