Subtract 9/21 from 54/72, Solve 54/72

Subtract 9/21 from 54/72

54/72 - 9/21 is 9/28.

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,
54/72 = 54 × 7/72 × 7 = 378/504
Likewise, for the 2nd fraction, since 21 × 24 = 504,
9/21 = 9 × 24/21 × 24 = 216/504
Subtract the two like fractions:
378/504 - 216/504 = 378 - 216/504 = 162/504
After reducing the fraction, the answer is 9/28

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