Add 72/9 and 90/12
1st number: 8 0/9, 2nd number: 7 6/12
72/9 + 90/12 is 31/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 12 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 9 × 4 = 36,
72/9 = 72 × 4/9 × 4 = 288/36 - Likewise, for the 2nd fraction, since 12 × 3 = 36,
90/12 = 90 × 3/12 × 3 = 270/36 - Add the two like fractions:
288/36 + 270/36 = 288 + 270/36 = 558/36 - 558/36 simplified gives 31/2
- So, 72/9 + 90/12 = 31/2
In mixed form: 151/2
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