Subtract 81/12 from 70/50, Solve 1 20/50

Subtract 81/12 from 70/50

1^st number: 1 20/50, 2^nd number: 6 9/12

70/50 - 81/12 is -107/20.

Find the least common denominator or LCM of the two denominators:
LCM of 50 and 12 is 300

Next, find the equivalent fraction of both fractional numbers with denominator 300
For the 1st fraction, since 50 × 6 = 300,
70/50 = 70 × 6/50 × 6 = 420/300
Likewise, for the 2nd fraction, since 12 × 25 = 300,
81/12 = 81 × 25/12 × 25 = 2025/300
Subtract the two like fractions:
420/300 - 2025/300 = 420 - 2025/300 = -1605/300
After reducing the fraction, the answer is -107/20

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