Add 15/18 and 21/20
1st number: 15/18, 2nd number: 1 1/20
15/18 + 21/20 is 113/60.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 18 × 10 = 180,
15/18 = 15 × 10/18 × 10 = 150/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Add the two like fractions:
150/180 + 189/180 = 150 + 189/180 = 339/180 - 339/180 simplified gives 113/60
- So, 15/18 + 21/20 = 113/60
In mixed form: 153/60
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