Add 20/72 and 21/18
1st number: 20/72, 2nd number: 1 3/18
20/72 + 21/18 is 13/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 18 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 72 × 1 = 72,
20/72 = 20 × 1/72 × 1 = 20/72 - Likewise, for the 2nd fraction, since 18 × 4 = 72,
21/18 = 21 × 4/18 × 4 = 84/72 - Add the two like fractions:
20/72 + 84/72 = 20 + 84/72 = 104/72 - 104/72 simplified gives 13/9
- So, 20/72 + 21/18 = 13/9
In mixed form: 14/9
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