Subtract 18/8 from 72/90
1st number: 72/90, 2nd number: 2 2/8
72/90 - 18/8 is -29/20.
Steps for subtracting fractions
- 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,
72/90 = 72 × 4/90 × 4 = 288/360 - Likewise, for the 2nd fraction, since 8 × 45 = 360,
18/8 = 18 × 45/8 × 45 = 810/360 - Subtract the two like fractions:
288/360 - 810/360 = 288 - 810/360 = -522/360 - After reducing the fraction, the answer is -29/20
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