Add 30/80 and 81/72
1st number: 30/80, 2nd number: 1 9/72
30/80 + 81/72 is 3/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 72 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
30/80 = 30 × 9/80 × 9 = 270/720 - Likewise, for the 2nd fraction, since 72 × 10 = 720,
81/72 = 81 × 10/72 × 10 = 810/720 - Add the two like fractions:
270/720 + 810/720 = 270 + 810/720 = 1080/720 - 1080/720 simplified gives 3/2
- So, 30/80 + 81/72 = 3/2
In mixed form: 11/2
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