Subtract 21/30 from 21/75
21/75 - 21/30 is -21/50.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 30 is 150
Next, find the equivalent fraction of both fractional numbers with denominator 150 - For the 1st fraction, since 75 × 2 = 150,
21/75 = 21 × 2/75 × 2 = 42/150 - Likewise, for the 2nd fraction, since 30 × 5 = 150,
21/30 = 21 × 5/30 × 5 = 105/150 - Subtract the two like fractions:
42/150 - 105/150 = 42 - 105/150 = -63/150 - After reducing the fraction, the answer is -21/50
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