Add 21/54 and 15/42
21/54 + 15/42 is 47/63.
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,
15/42 = 15 × 9/42 × 9 = 135/378 - Add the two like fractions:
147/378 + 135/378 = 147 + 135/378 = 282/378 - 282/378 simplified gives 47/63
- So, 21/54 + 15/42 = 47/63
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