Add 18/72 and 21/15
1st number: 18/72, 2nd number: 1 6/15
18/72 + 21/15 is 33/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 15 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
18/72 = 18 × 5/72 × 5 = 90/360 - Likewise, for the 2nd fraction, since 15 × 24 = 360,
21/15 = 21 × 24/15 × 24 = 504/360 - Add the two like fractions:
90/360 + 504/360 = 90 + 504/360 = 594/360 - 594/360 simplified gives 33/20
- So, 18/72 + 21/15 = 33/20
In mixed form: 113/20
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