Subtract 42/90 from 8/72
8/72 - 42/90 is -16/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
8/72 = 8 × 5/72 × 5 = 40/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
42/90 = 42 × 4/90 × 4 = 168/360 - Subtract the two like fractions:
40/360 - 168/360 = 40 - 168/360 = -128/360 - After reducing the fraction, the answer is -16/45
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