Subtract 21/75 from 1/90
1/90 - 21/75 is -121/450.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 75 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 90 × 5 = 450,
1/90 = 1 × 5/90 × 5 = 5/450 - Likewise, for the 2nd fraction, since 75 × 6 = 450,
21/75 = 21 × 6/75 × 6 = 126/450 - Subtract the two like fractions:
5/450 - 126/450 = 5 - 126/450 = -121/450
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