Subtract 18/42 from 63/20, Solve 3 3/20

Subtract 18/42 from 63/20

1^st number: 3 3/20, 2^nd number: 18/42

63/20 - 18/42 is 381/140.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
63/20 = 63 × 21/20 × 21 = 1323/420
Likewise, for the 2nd fraction, since 42 × 10 = 420,
18/42 = 18 × 10/42 × 10 = 180/420
Subtract the two like fractions:
1323/420 - 180/420 = 1323 - 180/420 = 1143/420
After reducing the fraction, the answer is 381/140
In mixed form: 2101/140

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