Subtract 81/42 from 28/50, Solve 28/50

Subtract 81/42 from 28/50

1^st number: 28/50, 2^nd number: 1 39/42

28/50 - 81/42 is -479/350.

Find the least common denominator or LCM of the two denominators:
LCM of 50 and 42 is 1050

Next, find the equivalent fraction of both fractional numbers with denominator 1050
For the 1st fraction, since 50 × 21 = 1050,
28/50 = 28 × 21/50 × 21 = 588/1050
Likewise, for the 2nd fraction, since 42 × 25 = 1050,
81/42 = 81 × 25/42 × 25 = 2025/1050
Subtract the two like fractions:
588/1050 - 2025/1050 = 588 - 2025/1050 = -1437/1050
After reducing the fraction, the answer is -479/350

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