Subtract 18/7 from 3/90, Solve 3/90

Subtract 18/7 from 3/90

1^st number: 3/90, 2^nd number: 2 4/7

3/90 - 18/7 is -533/210.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 7 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 90 × 7 = 630,
3/90 = 3 × 7/90 × 7 = 21/630
Likewise, for the 2nd fraction, since 7 × 90 = 630,
18/7 = 18 × 90/7 × 90 = 1620/630
Subtract the two like fractions:
21/630 - 1620/630 = 21 - 1620/630 = -1599/630
After reducing the fraction, the answer is -533/210

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