Subtract 7/20 from 42/75
42/75 - 7/20 is 21/100.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 20 is 300
Next, find the equivalent fraction of both fractional numbers with denominator 300 - For the 1st fraction, since 75 × 4 = 300,
42/75 = 42 × 4/75 × 4 = 168/300 - Likewise, for the 2nd fraction, since 20 × 15 = 300,
7/20 = 7 × 15/20 × 15 = 105/300 - Subtract the two like fractions:
168/300 - 105/300 = 168 - 105/300 = 63/300 - After reducing the fraction, the answer is 21/100
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