Add 15/80 and 81/72
1st number: 15/80, 2nd number: 1 9/72
15/80 + 81/72 is 21/16.
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,
15/80 = 15 × 9/80 × 9 = 135/720 - Likewise, for the 2nd fraction, since 72 × 10 = 720,
81/72 = 81 × 10/72 × 10 = 810/720 - Add the two like fractions:
135/720 + 810/720 = 135 + 810/720 = 945/720 - 945/720 simplified gives 21/16
- So, 15/80 + 81/72 = 21/16
In mixed form: 15/16
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