Add 21/15 and 20/18
1st number: 1 6/15, 2nd number: 1 2/18
21/15 + 20/18 is 113/45.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 15 × 6 = 90,
21/15 = 21 × 6/15 × 6 = 126/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
20/18 = 20 × 5/18 × 5 = 100/90 - Add the two like fractions:
126/90 + 100/90 = 126 + 100/90 = 226/90 - 226/90 simplified gives 113/45
- So, 21/15 + 20/18 = 113/45
In mixed form: 223/45
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