Subtract 72/50 from 21/90
1st number: 21/90, 2nd number: 1 22/50
21/90 - 72/50 is -181/150.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 50 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 90 × 5 = 450,
21/90 = 21 × 5/90 × 5 = 105/450 - Likewise, for the 2nd fraction, since 50 × 9 = 450,
72/50 = 72 × 9/50 × 9 = 648/450 - Subtract the two like fractions:
105/450 - 648/450 = 105 - 648/450 = -543/450 - After reducing the fraction, the answer is -181/150
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