Add 90/20 and 81/12
1st number: 4 10/20, 2nd number: 6 9/12
90/20 + 81/12 is 45/4.
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,
81/12 = 81 × 5/12 × 5 = 405/60 - Add the two like fractions:
270/60 + 405/60 = 270 + 405/60 = 675/60 - 675/60 simplified gives 45/4
- So, 90/20 + 81/12 = 45/4
In mixed form: 111/4
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