Add 15/42 and 21/81
15/42 + 21/81 is 233/378.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 81 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 42 × 27 = 1134,
15/42 = 15 × 27/42 × 27 = 405/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
21/81 = 21 × 14/81 × 14 = 294/1134 - Add the two like fractions:
405/1134 + 294/1134 = 405 + 294/1134 = 699/1134 - 699/1134 simplified gives 233/378
- So, 15/42 + 21/81 = 233/378
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