Subtract 30/84 from 7/90, Solve 7/90

Subtract 30/84 from 7/90

7/90 - 30/84 is -88/315.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 84 is 1260

Next, find the equivalent fraction of both fractional numbers with denominator 1260
For the 1st fraction, since 90 × 14 = 1260,
7/90 = 7 × 14/90 × 14 = 98/1260
Likewise, for the 2nd fraction, since 84 × 15 = 1260,
30/84 = 30 × 15/84 × 15 = 450/1260
Subtract the two like fractions:
98/1260 - 450/1260 = 98 - 450/1260 = -352/1260
After reducing the fraction, the answer is -88/315

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