Add 21/12 and 90/25
1st number: 1 9/12, 2nd number: 3 15/25
21/12 + 90/25 is 107/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 25 is 300
Next, find the equivalent fraction of both fractional numbers with denominator 300 - For the 1st fraction, since 12 × 25 = 300,
21/12 = 21 × 25/12 × 25 = 525/300 - Likewise, for the 2nd fraction, since 25 × 12 = 300,
90/25 = 90 × 12/25 × 12 = 1080/300 - Add the two like fractions:
525/300 + 1080/300 = 525 + 1080/300 = 1605/300 - 1605/300 simplified gives 107/20
- So, 21/12 + 90/25 = 107/20
In mixed form: 57/20
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