Add 21/54 and 90/7
1st number: 21/54, 2nd number: 12 6/7
21/54 + 90/7 is 1669/126.
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,
90/7 = 90 × 54/7 × 54 = 4860/378 - Add the two like fractions:
147/378 + 4860/378 = 147 + 4860/378 = 5007/378 - 5007/378 simplified gives 1669/126
- So, 21/54 + 90/7 = 1669/126
In mixed form: 1331/126
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