Add 81/12 and 90/70
1st number: 6 9/12, 2nd number: 1 20/70
81/12 + 90/70 is 225/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 12 × 35 = 420,
81/12 = 81 × 35/12 × 35 = 2835/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
90/70 = 90 × 6/70 × 6 = 540/420 - Add the two like fractions:
2835/420 + 540/420 = 2835 + 540/420 = 3375/420 - 3375/420 simplified gives 225/28
- So, 81/12 + 90/70 = 225/28
In mixed form: 81/28
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