Add 18/54 and 15/21
18/54 + 15/21 is 22/21.
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,
18/54 = 18 × 7/54 × 7 = 126/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
15/21 = 15 × 18/21 × 18 = 270/378 - Add the two like fractions:
126/378 + 270/378 = 126 + 270/378 = 396/378 - 396/378 simplified gives 22/21
- So, 18/54 + 15/21 = 22/21
In mixed form: 11/21
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