Add 21/72 and 15/20
21/72 + 15/20 is 25/24.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 20 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
21/72 = 21 × 5/72 × 5 = 105/360 - Likewise, for the 2nd fraction, since 20 × 18 = 360,
15/20 = 15 × 18/20 × 18 = 270/360 - Add the two like fractions:
105/360 + 270/360 = 105 + 270/360 = 375/360 - 375/360 simplified gives 25/24
- So, 21/72 + 15/20 = 25/24
In mixed form: 11/24
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