Subtract 18/72 from 21/50
21/50 - 18/72 is 17/100.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 72 is 1800
Next, find the equivalent fraction of both fractional numbers with denominator 1800 - For the 1st fraction, since 50 × 36 = 1800,
21/50 = 21 × 36/50 × 36 = 756/1800 - Likewise, for the 2nd fraction, since 72 × 25 = 1800,
18/72 = 18 × 25/72 × 25 = 450/1800 - Subtract the two like fractions:
756/1800 - 450/1800 = 756 - 450/1800 = 306/1800 - After reducing the fraction, the answer is 17/100
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