Add 21/12 and 90/9
1st number: 1 9/12, 2nd number: 10 0/9
21/12 + 90/9 is 47/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 9 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 12 × 3 = 36,
21/12 = 21 × 3/12 × 3 = 63/36 - Likewise, for the 2nd fraction, since 9 × 4 = 36,
90/9 = 90 × 4/9 × 4 = 360/36 - Add the two like fractions:
63/36 + 360/36 = 63 + 360/36 = 423/36 - 423/36 simplified gives 47/4
- So, 21/12 + 90/9 = 47/4
In mixed form: 113/4
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