Subtract 18/21 from 30/75
30/75 - 18/21 is -16/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 21 is 525
Next, find the equivalent fraction of both fractional numbers with denominator 525 - For the 1st fraction, since 75 × 7 = 525,
30/75 = 30 × 7/75 × 7 = 210/525 - Likewise, for the 2nd fraction, since 21 × 25 = 525,
18/21 = 18 × 25/21 × 25 = 450/525 - Subtract the two like fractions:
210/525 - 450/525 = 210 - 450/525 = -240/525 - After reducing the fraction, the answer is -16/35
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