Add 21/27 and 7/42
21/27 + 7/42 is 17/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 42 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 27 × 14 = 378,
21/27 = 21 × 14/27 × 14 = 294/378 - Likewise, for the 2nd fraction, since 42 × 9 = 378,
7/42 = 7 × 9/42 × 9 = 63/378 - Add the two like fractions:
294/378 + 63/378 = 294 + 63/378 = 357/378 - 357/378 simplified gives 17/18
- So, 21/27 + 7/42 = 17/18
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