Add 42/21 and 81/36
1st number: 2 0/21, 2nd number: 2 9/36
42/21 + 81/36 is 17/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 21 × 12 = 252,
42/21 = 42 × 12/21 × 12 = 504/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
81/36 = 81 × 7/36 × 7 = 567/252 - Add the two like fractions:
504/252 + 567/252 = 504 + 567/252 = 1071/252 - 1071/252 simplified gives 17/4
- So, 42/21 + 81/36 = 17/4
In mixed form: 41/4
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