Add 81/90 and 12/72
81/90 + 12/72 is 16/15.
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,
12/72 = 12 × 5/72 × 5 = 60/360 - Add the two like fractions:
324/360 + 60/360 = 324 + 60/360 = 384/360 - 384/360 simplified gives 16/15
- So, 81/90 + 12/72 = 16/15
In mixed form: 11/15
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