Add 21/12 and 90/20
1st number: 1 9/12, 2nd number: 4 10/20
21/12 + 90/20 is 25/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 20 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
21/12 = 21 × 5/12 × 5 = 105/60 - Likewise, for the 2nd fraction, since 20 × 3 = 60,
90/20 = 90 × 3/20 × 3 = 270/60 - Add the two like fractions:
105/60 + 270/60 = 105 + 270/60 = 375/60 - 375/60 simplified gives 25/4
- So, 21/12 + 90/20 = 25/4
In mixed form: 61/4
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