Subtract 21/8 from 75/54, Solve 1 21/54

Subtract 21/8 from 75/54

1^st number: 1 21/54, 2^nd number: 2 5/8

75/54 - 21/8 is -89/72.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 8 is 216

Next, find the equivalent fraction of both fractional numbers with denominator 216
For the 1st fraction, since 54 × 4 = 216,
75/54 = 75 × 4/54 × 4 = 300/216
Likewise, for the 2nd fraction, since 8 × 27 = 216,
21/8 = 21 × 27/8 × 27 = 567/216
Subtract the two like fractions:
300/216 - 567/216 = 300 - 567/216 = -267/216
After reducing the fraction, the answer is -89/72

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