Subtract 3/45 from 8/21, Solve 8/21

Subtract 3/45 from 8/21

8/21 - 3/45 is 11/35.

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,
8/21 = 8 × 15/21 × 15 = 120/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
3/45 = 3 × 7/45 × 7 = 21/315
Subtract the two like fractions:
120/315 - 21/315 = 120 - 21/315 = 99/315
After reducing the fraction, the answer is 11/35

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