Add 15/20 and 81/72
1st number: 15/20, 2nd number: 1 9/72
15/20 + 81/72 is 15/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 20 × 18 = 360,
15/20 = 15 × 18/20 × 18 = 270/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
81/72 = 81 × 5/72 × 5 = 405/360 - Add the two like fractions:
270/360 + 405/360 = 270 + 405/360 = 675/360 - 675/360 simplified gives 15/8
- So, 15/20 + 81/72 = 15/8
In mixed form: 17/8
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