Add 21/12 and 90/15
1st number: 1 9/12, 2nd number: 6 0/15
21/12 + 90/15 is 31/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 15 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
21/12 = 21 × 5/12 × 5 = 105/60 - Likewise, for the 2nd fraction, since 15 × 4 = 60,
90/15 = 90 × 4/15 × 4 = 360/60 - Add the two like fractions:
105/60 + 360/60 = 105 + 360/60 = 465/60 - 465/60 simplified gives 31/4
- So, 21/12 + 90/15 = 31/4
In mixed form: 73/4
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