Add 21/54 and 70/21
1st number: 21/54, 2nd number: 3 7/21
21/54 + 70/21 is 67/18.
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,
70/21 = 70 × 18/21 × 18 = 1260/378 - Add the two like fractions:
147/378 + 1260/378 = 147 + 1260/378 = 1407/378 - 1407/378 simplified gives 67/18
- So, 21/54 + 70/21 = 67/18
In mixed form: 313/18
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