Add 15/54 and 7/21
15/54 + 7/21 is 11/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
15/54 = 15 × 7/54 × 7 = 105/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
7/21 = 7 × 18/21 × 18 = 126/378 - Add the two like fractions:
105/378 + 126/378 = 105 + 126/378 = 231/378 - 231/378 simplified gives 11/18
- So, 15/54 + 7/21 = 11/18
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