Subtract 28/30 from 40/72
40/72 - 28/30 is -17/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 30 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
40/72 = 40 × 5/72 × 5 = 200/360 - Likewise, for the 2nd fraction, since 30 × 12 = 360,
28/30 = 28 × 12/30 × 12 = 336/360 - Subtract the two like fractions:
200/360 - 336/360 = 200 - 336/360 = -136/360 - After reducing the fraction, the answer is -17/45
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