Subtract 42/90 from 7/8, Solve 7/8

Subtract 42/90 from 7/8

7/8 - 42/90 is 49/120.

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

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 8 × 45 = 360,
7/8 = 7 × 45/8 × 45 = 315/360
Likewise, for the 2nd fraction, since 90 × 4 = 360,
42/90 = 42 × 4/90 × 4 = 168/360
Subtract the two like fractions:
315/360 - 168/360 = 315 - 168/360 = 147/360
After reducing the fraction, the answer is 49/120

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