Add 42/21 and 63/18
1st number: 2 0/21, 2nd number: 3 9/18
42/21 + 63/18 is 11/2.
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,
63/18 = 63 × 7/18 × 7 = 441/126 - Add the two like fractions:
252/126 + 441/126 = 252 + 441/126 = 693/126 - 693/126 simplified gives 11/2
- So, 42/21 + 63/18 = 11/2
In mixed form: 51/2
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