Add 90/12 and 81/72
1st number: 7 6/12, 2nd number: 1 9/72
90/12 + 81/72 is 69/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 12 × 6 = 72,
90/12 = 90 × 6/12 × 6 = 540/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
81/72 = 81 × 1/72 × 1 = 81/72 - Add the two like fractions:
540/72 + 81/72 = 540 + 81/72 = 621/72 - 621/72 simplified gives 69/8
- So, 90/12 + 81/72 = 69/8
In mixed form: 85/8
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