Add 21/42 and 30/54
21/42 + 30/54 is 19/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 42 × 9 = 378,
21/42 = 21 × 9/42 × 9 = 189/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
30/54 = 30 × 7/54 × 7 = 210/378 - Add the two like fractions:
189/378 + 210/378 = 189 + 210/378 = 399/378 - 399/378 simplified gives 19/18
- So, 21/42 + 30/54 = 19/18
In mixed form: 11/18
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