Add 42/21 and 21/18
1st number: 2 0/21, 2nd number: 1 3/18
42/21 + 21/18 is 19/6.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
42/21 = 42 × 6/21 × 6 = 252/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126 - Add the two like fractions:
252/126 + 147/126 = 252 + 147/126 = 399/126 - 399/126 simplified gives 19/6
- So, 42/21 + 21/18 = 19/6
In mixed form: 31/6
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