Add 21/42 and 21/27
21/42 + 21/27 is 23/18.
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,
21/27 = 21 × 14/27 × 14 = 294/378 - Add the two like fractions:
189/378 + 294/378 = 189 + 294/378 = 483/378 - 483/378 simplified gives 23/18
- So, 21/42 + 21/27 = 23/18
In mixed form: 15/18
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