Add 15/21 and 20/54
15/21 + 20/54 is 205/189.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 21 × 18 = 378,
15/21 = 15 × 18/21 × 18 = 270/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
20/54 = 20 × 7/54 × 7 = 140/378 - Add the two like fractions:
270/378 + 140/378 = 270 + 140/378 = 410/378 - 410/378 simplified gives 205/189
- So, 15/21 + 20/54 = 205/189
In mixed form: 116/189
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