Subtract 9/21 from 9/72
972 - 921 is -1756.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
972 = 9 × 772 × 7 = 63504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
921 = 9 × 2421 × 24 = 216504 - Subtract the two like fractions:
63504 - 216504 = 63 - 216504 = -153504 - After reducing the fraction, the answer is -1756
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