Add 21/54 and 42/63
21/54 + 42/63 is 19/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 63 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
21/54 = 21 × 7/54 × 7 = 147/378 - Likewise, for the 2nd fraction, since 63 × 6 = 378,
42/63 = 42 × 6/63 × 6 = 252/378 - Add the two like fractions:
147/378 + 252/378 = 147 + 252/378 = 399/378 - 399/378 simplified gives 19/18
- So, 21/54 + 42/63 = 19/18
In mixed form: 11/18
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