Add 81/90 and 18/72
81/90 + 18/72 is 23/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
81/90 = 81 × 4/90 × 4 = 324/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
18/72 = 18 × 5/72 × 5 = 90/360 - Add the two like fractions:
324/360 + 90/360 = 324 + 90/360 = 414/360 - 414/360 simplified gives 23/20
- So, 81/90 + 18/72 = 23/20
In mixed form: 13/20
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