Subtract 18/72 from 21/15
1st number: 1 6/15, 2nd number: 18/72
21/15 - 18/72 is 23/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 15 × 24 = 360,
21/15 = 21 × 24/15 × 24 = 504/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
18/72 = 18 × 5/72 × 5 = 90/360 - Subtract the two like fractions:
504/360 - 90/360 = 504 - 90/360 = 414/360 - After reducing the fraction, the answer is 23/20
- In mixed form: 13/20
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