Add 90/12 and 21/15
1st number: 7 6/12, 2nd number: 1 6/15
90/12 + 21/15 is 89/10.
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,
90/12 = 90 × 5/12 × 5 = 450/60 - Likewise, for the 2nd fraction, since 15 × 4 = 60,
21/15 = 21 × 4/15 × 4 = 84/60 - Add the two like fractions:
450/60 + 84/60 = 450 + 84/60 = 534/60 - 534/60 simplified gives 89/10
- So, 90/12 + 21/15 = 89/10
In mixed form: 89/10
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