Subtract 20/45 from 45/21, Solve 2 3/21

Subtract 20/45 from 45/21

1^st number: 2 3/21, 2^nd number: 20/45

45/21 - 20/45 is 107/63.

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,
45/21 = 45 × 15/21 × 15 = 675/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
20/45 = 20 × 7/45 × 7 = 140/315
Subtract the two like fractions:
675/315 - 140/315 = 675 - 140/315 = 535/315
After reducing the fraction, the answer is 107/63
In mixed form: 144/63

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