Subtract 15/21 from 20/50, Solve 20/50

Subtract 15/21 from 20/50

20/50 - 15/21 is -11/35.

Find the least common denominator or LCM of the two denominators:
LCM of 50 and 21 is 1050

Next, find the equivalent fraction of both fractional numbers with denominator 1050
For the 1st fraction, since 50 × 21 = 1050,
20/50 = 20 × 21/50 × 21 = 420/1050
Likewise, for the 2nd fraction, since 21 × 50 = 1050,
15/21 = 15 × 50/21 × 50 = 750/1050
Subtract the two like fractions:
420/1050 - 750/1050 = 420 - 750/1050 = -330/1050
After reducing the fraction, the answer is -11/35

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