Add 81/7 and 90/8
1st number: 11 4/7, 2nd number: 11 2/8
81/7 + 90/8 is 639/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 8 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 7 × 8 = 56,
81/7 = 81 × 8/7 × 8 = 648/56 - Likewise, for the 2nd fraction, since 8 × 7 = 56,
90/8 = 90 × 7/8 × 7 = 630/56 - Add the two like fractions:
648/56 + 630/56 = 648 + 630/56 = 1278/56 - 1278/56 simplified gives 639/28
- So, 81/7 + 90/8 = 639/28
In mixed form: 2223/28
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