Subtract 40/50 from 21/72
21/72 - 40/50 is -61/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 50 is 1800
Next, find the equivalent fraction of both fractional numbers with denominator 1800 - For the 1st fraction, since 72 × 25 = 1800,
21/72 = 21 × 25/72 × 25 = 525/1800 - Likewise, for the 2nd fraction, since 50 × 36 = 1800,
40/50 = 40 × 36/50 × 36 = 1440/1800 - Subtract the two like fractions:
525/1800 - 1440/1800 = 525 - 1440/1800 = -915/1800 - After reducing the fraction, the answer is -61/120
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