Add 81/90 and 70/80
81/90 + 70/80 is 71/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
81/90 = 81 × 8/90 × 8 = 648/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
70/80 = 70 × 9/80 × 9 = 630/720 - Add the two like fractions:
648/720 + 630/720 = 648 + 630/720 = 1278/720 - 1278/720 simplified gives 71/40
- So, 81/90 + 70/80 = 71/40
In mixed form: 131/40
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