Subtract 21/25 from 18/28
18/28 - 21/25 is -69/350.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 25 is 700
Next, find the equivalent fraction of both fractional numbers with denominator 700 - For the 1st fraction, since 28 × 25 = 700,
18/28 = 18 × 25/28 × 25 = 450/700 - Likewise, for the 2nd fraction, since 25 × 28 = 700,
21/25 = 21 × 28/25 × 28 = 588/700 - Subtract the two like fractions:
450/700 - 588/700 = 450 - 588/700 = -138/700 - After reducing the fraction, the answer is -69/350
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