Add 21/42 and 3/27
21/42 + 3/27 is 11/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 27 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 42 × 9 = 378,
21/42 = 21 × 9/42 × 9 = 189/378 - Likewise, for the 2nd fraction, since 27 × 14 = 378,
3/27 = 3 × 14/27 × 14 = 42/378 - Add the two like fractions:
189/378 + 42/378 = 189 + 42/378 = 231/378 - 231/378 simplified gives 11/18
- So, 21/42 + 3/27 = 11/18
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