Subtract 49/20 from 3/21, Solve 3/21

Subtract 49/20 from 3/21

1^st number: 3/21, 2^nd number: 2 9/20

3/21 - 49/20 is -323/140.

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,
3/21 = 3 × 20/21 × 20 = 60/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
49/20 = 49 × 21/20 × 21 = 1029/420
Subtract the two like fractions:
60/420 - 1029/420 = 60 - 1029/420 = -969/420
After reducing the fraction, the answer is -323/140

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