Subtract 50/20 from 4/21, Solve 4/21

Subtract 50/20 from 4/21

1^st number: 4/21, 2^nd number: 2 10/20

4/21 - 50/20 is -97/42.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
4/21 = 4 × 20/21 × 20 = 80/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
50/20 = 50 × 21/20 × 21 = 1050/420
Subtract the two like fractions:
80/420 - 1050/420 = 80 - 1050/420 = -970/420
After reducing the fraction, the answer is -97/42

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