Subtract 21/30 from 72/18
1st number: 4 0/18, 2nd number: 21/30
72/18 - 21/30 is 33/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 30 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
72/18 = 72 × 5/18 × 5 = 360/90 - Likewise, for the 2nd fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Subtract the two like fractions:
360/90 - 63/90 = 360 - 63/90 = 297/90 - After reducing the fraction, the answer is 33/10
- In mixed form: 33/10
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