Subtract 45/20 from 21/72
1st number: 21/72, 2nd number: 2 5/20
21/72 - 45/20 is -47/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 20 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
21/72 = 21 × 5/72 × 5 = 105/360 - Likewise, for the 2nd fraction, since 20 × 18 = 360,
45/20 = 45 × 18/20 × 18 = 810/360 - Subtract the two like fractions:
105/360 - 810/360 = 105 - 810/360 = -705/360 - After reducing the fraction, the answer is -47/24
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