Subtract 21/12 from 70/50, Solve 1 20/50

Subtract 21/12 from 70/50

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

70/50 - 21/12 is -7/20.

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,
21/12 = 21 × 25/12 × 25 = 525/300
Subtract the two like fractions:
420/300 - 525/300 = 420 - 525/300 = -105/300
After reducing the fraction, the answer is -7/20

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