Subtract 20/45 from 21/75
21/75 - 20/45 is -37/225.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 45 is 225
Next, find the equivalent fraction of both fractional numbers with denominator 225 - For the 1st fraction, since 75 × 3 = 225,
21/75 = 21 × 3/75 × 3 = 63/225 - Likewise, for the 2nd fraction, since 45 × 5 = 225,
20/45 = 20 × 5/45 × 5 = 100/225 - Subtract the two like fractions:
63/225 - 100/225 = 63 - 100/225 = -37/225
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