Add 21/54 and 3/42
21/54 + 3/42 is 29/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 42 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 42 × 9 = 378,
3/42 = 3 × 9/42 × 9 = 27/378 - Add the two like fractions:
147/378 + 27/378 = 147 + 27/378 = 174/378 - 174/378 simplified gives 29/63
- So, 21/54 + 3/42 = 29/63
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