Add 30/42 and 21/54
30/42 + 21/54 is 139/126.
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,
30/42 = 30 × 9/42 × 9 = 270/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
21/54 = 21 × 7/54 × 7 = 147/378 - Add the two like fractions:
270/378 + 147/378 = 270 + 147/378 = 417/378 - 417/378 simplified gives 139/126
- So, 30/42 + 21/54 = 139/126
In mixed form: 113/126
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