Add 20/36 and 42/21
1st number: 20/36, 2nd number: 2 0/21
20/36 + 42/21 is 23/9.
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,
20/36 = 20 × 7/36 × 7 = 140/252 - Likewise, for the 2nd fraction, since 21 × 12 = 252,
42/21 = 42 × 12/21 × 12 = 504/252 - Add the two like fractions:
140/252 + 504/252 = 140 + 504/252 = 644/252 - 644/252 simplified gives 23/9
- So, 20/36 + 42/21 = 23/9
In mixed form: 25/9
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