Subtract 70/90 from 21/50
21/50 - 70/90 is -161/450.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 90 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 50 × 9 = 450,
21/50 = 21 × 9/50 × 9 = 189/450 - Likewise, for the 2nd fraction, since 90 × 5 = 450,
70/90 = 70 × 5/90 × 5 = 350/450 - Subtract the two like fractions:
189/450 - 350/450 = 189 - 350/450 = -161/450
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