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

Subtract 21/45 from 2/21

2/21 - 21/45 is -13/35.

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,
2/21 = 2 × 15/21 × 15 = 30/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315
Subtract the two like fractions:
30/315 - 147/315 = 30 - 147/315 = -117/315
After reducing the fraction, the answer is -13/35

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