Subtract 21/90 from 72/40
1st number: 1 32/40, 2nd number: 21/90
72/40 - 21/90 is 47/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
72/40 = 72 × 9/40 × 9 = 648/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
21/90 = 21 × 4/90 × 4 = 84/360 - Subtract the two like fractions:
648/360 - 84/360 = 648 - 84/360 = 564/360 - After reducing the fraction, the answer is 47/30
- In mixed form: 117/30
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