Add 21/12 and 12/90
1st number: 1 9/12, 2nd number: 12/90
21/12 + 12/90 is 113/60.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 12 × 15 = 180,
21/12 = 21 × 15/12 × 15 = 315/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
12/90 = 12 × 2/90 × 2 = 24/180 - Add the two like fractions:
315/180 + 24/180 = 315 + 24/180 = 339/180 - 339/180 simplified gives 113/60
- So, 21/12 + 12/90 = 113/60
In mixed form: 153/60
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