Subtract 12/20 from 24/21, Solve 1 3/21

Subtract 12/20 from 24/21

1^st number: 1 3/21, 2^nd number: 12/20

24/21 - 12/20 is 19/35.

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,
24/21 = 24 × 20/21 × 20 = 480/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
12/20 = 12 × 21/20 × 21 = 252/420
Subtract the two like fractions:
480/420 - 252/420 = 480 - 252/420 = 228/420
After reducing the fraction, the answer is 19/35

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