Add 7/8 and 81/90
7/8 + 81/90 is 71/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 8 × 45 = 360,
7/8 = 7 × 45/8 × 45 = 315/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
81/90 = 81 × 4/90 × 4 = 324/360 - Add the two like fractions:
315/360 + 324/360 = 315 + 324/360 = 639/360 - 639/360 simplified gives 71/40
- So, 7/8 + 81/90 = 71/40
In mixed form: 131/40
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