Subtract 70/90 from 21/75
21/75 - 70/90 is -112/225.
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,
21/75 = 21 × 6/75 × 6 = 126/450 - Likewise, for the 2nd fraction, since 90 × 5 = 450,
70/90 = 70 × 5/90 × 5 = 350/450 - Subtract the two like fractions:
126/450 - 350/450 = 126 - 350/450 = -224/450 - After reducing the fraction, the answer is -112/225
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