Add 20/21 and 21/54
20/21 + 21/54 is 169/126.
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,
21/54 = 21 × 7/54 × 7 = 147/378 - Add the two like fractions:
360/378 + 147/378 = 360 + 147/378 = 507/378 - 507/378 simplified gives 169/126
- So, 20/21 + 21/54 = 169/126
In mixed form: 143/126
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