Subtract 25/49 from 18/21
18/21 - 25/49 is 17/49.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 49 is 147
Next, find the equivalent fraction of both fractional numbers with denominator 147 - For the 1st fraction, since 21 × 7 = 147,
18/21 = 18 × 7/21 × 7 = 126/147 - Likewise, for the 2nd fraction, since 49 × 3 = 147,
25/49 = 25 × 3/49 × 3 = 75/147 - Subtract the two like fractions:
126/147 - 75/147 = 126 - 75/147 = 51/147 - After reducing the fraction, the answer is 17/49
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