Subtract 15/10 from 21/54, Solve 21/54

Subtract 15/10 from 21/54

1^st number: 21/54, 2^nd number: 1 5/10

21/54 - 15/10 is -10/9.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 10 is 270

Next, find the equivalent fraction of both fractional numbers with denominator 270
For the 1st fraction, since 54 × 5 = 270,
21/54 = 21 × 5/54 × 5 = 105/270
Likewise, for the 2nd fraction, since 10 × 27 = 270,
15/10 = 15 × 27/10 × 27 = 405/270
Subtract the two like fractions:
105/270 - 405/270 = 105 - 405/270 = -300/270
After reducing the fraction, the answer is -10/9

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