Subtract 12/45 from 24/21, Solve 1 3/21

Subtract 12/45 from 24/21

1^st number: 1 3/21, 2^nd number: 12/45

24/21 - 12/45 is 92/105.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 21 × 15 = 315,
24/21 = 24 × 15/21 × 15 = 360/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
12/45 = 12 × 7/45 × 7 = 84/315
Subtract the two like fractions:
360/315 - 84/315 = 360 - 84/315 = 276/315
After reducing the fraction, the answer is 92/105

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