Subtract 81/70 from 30/50, Solve 30/50

Subtract 81/70 from 30/50

1^st number: 30/50, 2^nd number: 1 11/70

30/50 - 81/70 is -39/70.

Find the least common denominator or LCM of the two denominators:
LCM of 50 and 70 is 350

Next, find the equivalent fraction of both fractional numbers with denominator 350
For the 1st fraction, since 50 × 7 = 350,
30/50 = 30 × 7/50 × 7 = 210/350
Likewise, for the 2nd fraction, since 70 × 5 = 350,
81/70 = 81 × 5/70 × 5 = 405/350
Subtract the two like fractions:
210/350 - 405/350 = 210 - 405/350 = -195/350
After reducing the fraction, the answer is -39/70

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