Subtract 21/90 from 12/75
12/75 - 21/90 is -11/150.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 90 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 75 × 6 = 450,
12/75 = 12 × 6/75 × 6 = 72/450 - Likewise, for the 2nd fraction, since 90 × 5 = 450,
21/90 = 21 × 5/90 × 5 = 105/450 - Subtract the two like fractions:
72/450 - 105/450 = 72 - 105/450 = -33/450 - After reducing the fraction, the answer is -11/150
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