Add 20/15 and 21/54
1st number: 1 5/15, 2nd number: 21/54
20/15 + 21/54 is 31/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 54 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 15 × 18 = 270,
20/15 = 20 × 18/15 × 18 = 360/270 - Likewise, for the 2nd fraction, since 54 × 5 = 270,
21/54 = 21 × 5/54 × 5 = 105/270 - Add the two like fractions:
360/270 + 105/270 = 360 + 105/270 = 465/270 - 465/270 simplified gives 31/18
- So, 20/15 + 21/54 = 31/18
In mixed form: 113/18
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