Add 21/54 and 45/21
1st number: 21/54, 2nd number: 2 3/21
21/54 + 45/21 is 319/126.
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,
21/54 = 21 × 7/54 × 7 = 147/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
45/21 = 45 × 18/21 × 18 = 810/378 - Add the two like fractions:
147/378 + 810/378 = 147 + 810/378 = 957/378 - 957/378 simplified gives 319/126
- So, 21/54 + 45/21 = 319/126
In mixed form: 267/126
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