Add 21/20 and 90/12
1st number: 1 1/20, 2nd number: 7 6/12
21/20 + 90/12 is 171/20.
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,
21/20 = 21 × 3/20 × 3 = 63/60 - Likewise, for the 2nd fraction, since 12 × 5 = 60,
90/12 = 90 × 5/12 × 5 = 450/60 - Add the two like fractions:
63/60 + 450/60 = 63 + 450/60 = 513/60 - 513/60 simplified gives 171/20
- So, 21/20 + 90/12 = 171/20
In mixed form: 811/20
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