Add 21/20 and 3/90
1st number: 1 1/20, 2nd number: 3/90
21/20 + 3/90 is 13/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 90 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 90 × 2 = 180,
3/90 = 3 × 2/90 × 2 = 6/180 - Add the two like fractions:
189/180 + 6/180 = 189 + 6/180 = 195/180 - 195/180 simplified gives 13/12
- So, 21/20 + 3/90 = 13/12
In mixed form: 11/12
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