Add 81/72 and 80/90
1st number: 1 9/72, 2nd number: 80/90
81/72 + 80/90 is 145/72.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
81/72 = 81 × 5/72 × 5 = 405/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
80/90 = 80 × 4/90 × 4 = 320/360 - Add the two like fractions:
405/360 + 320/360 = 405 + 320/360 = 725/360 - 725/360 simplified gives 145/72
- So, 81/72 + 80/90 = 145/72
In mixed form: 21/72
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