Subtract 21/30 from 3/90
3/90 - 21/30 is -2/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 30 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
3/90 = 3 × 1/90 × 1 = 3/90 - Likewise, for the 2nd fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Subtract the two like fractions:
3/90 - 63/90 = 3 - 63/90 = -60/90 - After reducing the fraction, the answer is -2/3
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