Subtract 80/8 from 7/90, Solve 7/90

Subtract 80/8 from 7/90

1^st number: 7/90, 2^nd number: 10 0/8

7/90 - 80/8 is -893/90.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 8 is 360

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 90 × 4 = 360,
7/90 = 7 × 4/90 × 4 = 28/360
Likewise, for the 2nd fraction, since 8 × 45 = 360,
80/8 = 80 × 45/8 × 45 = 3600/360
Subtract the two like fractions:
28/360 - 3600/360 = 28 - 3600/360 = -3572/360
After reducing the fraction, the answer is -893/90

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