Subtract 75/80 from 45/70
45/70 - 75/80 is -33/112.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 80 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 70 × 8 = 560,
45/70 = 45 × 8/70 × 8 = 360/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
75/80 = 75 × 7/80 × 7 = 525/560 - Subtract the two like fractions:
360/560 - 525/560 = 360 - 525/560 = -165/560 - After reducing the fraction, the answer is -33/112
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