Add 90/20 and 9/12
1st number: 4 10/20, 2nd number: 9/12
90/20 + 9/12 is 21/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 12 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 20 × 3 = 60,
90/20 = 90 × 3/20 × 3 = 270/60 - Likewise, for the 2nd fraction, since 12 × 5 = 60,
9/12 = 9 × 5/12 × 5 = 45/60 - Add the two like fractions:
270/60 + 45/60 = 270 + 45/60 = 315/60 - 315/60 simplified gives 21/4
- So, 90/20 + 9/12 = 21/4
In mixed form: 51/4
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