Subtract 18/90 from 3/72
3/72 - 18/90 is -19/120.
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,
3/72 = 3 × 5/72 × 5 = 15/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
18/90 = 18 × 4/90 × 4 = 72/360 - Subtract the two like fractions:
15/360 - 72/360 = 15 - 72/360 = -57/360 - After reducing the fraction, the answer is -19/120
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