Subtract 30/27 from 28/90, Solve 28/90

Subtract 30/27 from 28/90

1^st number: 28/90, 2^nd number: 1 3/27

28/90 - 30/27 is -4/5.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 27 is 270

Next, find the equivalent fraction of both fractional numbers with denominator 270
For the 1st fraction, since 90 × 3 = 270,
28/90 = 28 × 3/90 × 3 = 84/270
Likewise, for the 2nd fraction, since 27 × 10 = 270,
30/27 = 30 × 10/27 × 10 = 300/270
Subtract the two like fractions:
84/270 - 300/270 = 84 - 300/270 = -216/270
After reducing the fraction, the answer is -4/5

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