Subtract 21/45 from 15/54, Solve 15/54

Subtract 21/45 from 15/54

15/54 - 21/45 is -17/90.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 45 is 270

Next, find the equivalent fraction of both fractional numbers with denominator 270
For the 1st fraction, since 54 × 5 = 270,
15/54 = 15 × 5/54 × 5 = 75/270
Likewise, for the 2nd fraction, since 45 × 6 = 270,
21/45 = 21 × 6/45 × 6 = 126/270
Subtract the two like fractions:
75/270 - 126/270 = 75 - 126/270 = -51/270
After reducing the fraction, the answer is -17/90

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