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