Add 18/21 and 45/54
18/21 + 45/54 is 71/42.
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,
18/21 = 18 × 18/21 × 18 = 324/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
45/54 = 45 × 7/54 × 7 = 315/378 - Add the two like fractions:
324/378 + 315/378 = 324 + 315/378 = 639/378 - 639/378 simplified gives 71/42
- So, 18/21 + 45/54 = 71/42
In mixed form: 129/42
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