Subtract 25/8 from 21/27, Solve 21/27

Subtract 25/8 from 21/27

1^st number: 21/27, 2^nd number: 3 1/8

21/27 - 25/8 is -169/72.

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,
21/27 = 21 × 8/27 × 8 = 168/216
Likewise, for the 2nd fraction, since 8 × 27 = 216,
25/8 = 25 × 27/8 × 27 = 675/216
Subtract the two like fractions:
168/216 - 675/216 = 168 - 675/216 = -507/216
After reducing the fraction, the answer is -169/72

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