Add 30/36 and 40/21
1st number: 30/36, 2nd number: 1 19/21
30/36 + 40/21 is 115/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 21 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
30/36 = 30 × 7/36 × 7 = 210/252 - Likewise, for the 2nd fraction, since 21 × 12 = 252,
40/21 = 40 × 12/21 × 12 = 480/252 - Add the two like fractions:
210/252 + 480/252 = 210 + 480/252 = 690/252 - 690/252 simplified gives 115/42
- So, 30/36 + 40/21 = 115/42
In mixed form: 231/42
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