Subtract 2/90 from 18/21, Solve 18/21

Subtract 2/90 from 18/21

18/21 - 2/90 is 263/315.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 21 × 30 = 630,
18/21 = 18 × 30/21 × 30 = 540/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
2/90 = 2 × 7/90 × 7 = 14/630
Subtract the two like fractions:
540/630 - 14/630 = 540 - 14/630 = 526/630
After reducing the fraction, the answer is 263/315

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