Subtract 30/40 from 28/72
28/72 - 30/40 is -13/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
28/72 = 28 × 5/72 × 5 = 140/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
30/40 = 30 × 9/40 × 9 = 270/360 - Subtract the two like fractions:
140/360 - 270/360 = 140 - 270/360 = -130/360 - After reducing the fraction, the answer is -13/36
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