Subtract 42/32 from 7/81, Solve 7/81

Subtract 42/32 from 7/81

1^st number: 7/81, 2^nd number: 1 10/32

7/81 - 42/32 is -1589/1296.

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 32 is 2592

Next, find the equivalent fraction of both fractional numbers with denominator 2592
For the 1st fraction, since 81 × 32 = 2592,
7/81 = 7 × 32/81 × 32 = 224/2592
Likewise, for the 2nd fraction, since 32 × 81 = 2592,
42/32 = 42 × 81/32 × 81 = 3402/2592
Subtract the two like fractions:
224/2592 - 3402/2592 = 224 - 3402/2592 = -3178/2592
After reducing the fraction, the answer is -1589/1296

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