Add 21/20 and 90/9
1st number: 1 1/20, 2nd number: 10 0/9
21/20 + 90/9 is 221/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 9 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Likewise, for the 2nd fraction, since 9 × 20 = 180,
90/9 = 90 × 20/9 × 20 = 1800/180 - Add the two like fractions:
189/180 + 1800/180 = 189 + 1800/180 = 1989/180 - 1989/180 simplified gives 221/20
- So, 21/20 + 90/9 = 221/20
In mixed form: 111/20
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