Add 21/54 and 21/42
21/54 + 21/42 is 8/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 42 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 42 × 9 = 378,
21/42 = 21 × 9/42 × 9 = 189/378 - Add the two like fractions:
147/378 + 189/378 = 147 + 189/378 = 336/378 - 336/378 simplified gives 8/9
- So, 21/54 + 21/42 = 8/9
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