Add 20/21 and 18/36
20/21 + 18/36 is 61/42.
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,
20/21 = 20 × 12/21 × 12 = 240/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
18/36 = 18 × 7/36 × 7 = 126/252 - Add the two like fractions:
240/252 + 126/252 = 240 + 126/252 = 366/252 - 366/252 simplified gives 61/42
- So, 20/21 + 18/36 = 61/42
In mixed form: 119/42
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