Add 21/54 and 5/7
21/54 + 5/7 is 139/126.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 7 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 7 × 54 = 378,
5/7 = 5 × 54/7 × 54 = 270/378 - Add the two like fractions:
147/378 + 270/378 = 147 + 270/378 = 417/378 - 417/378 simplified gives 139/126
- So, 21/54 + 5/7 = 139/126
In mixed form: 113/126
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