Subtract 21/8 from 15/27, Solve 15/27

Subtract 21/8 from 15/27

1^st number: 15/27, 2^nd number: 2 5/8

15/27 - 21/8 is -149/72.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 8 is 216

Next, find the equivalent fraction of both fractional numbers with denominator 216
For the 1st fraction, since 27 × 8 = 216,
15/27 = 15 × 8/27 × 8 = 120/216
Likewise, for the 2nd fraction, since 8 × 27 = 216,
21/8 = 21 × 27/8 × 27 = 567/216
Subtract the two like fractions:
120/216 - 567/216 = 120 - 567/216 = -447/216
After reducing the fraction, the answer is -149/72

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