Subtract 42/80 from 30/70
30/70 - 42/80 is -27/280.
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,
30/70 = 30 × 8/70 × 8 = 240/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
42/80 = 42 × 7/80 × 7 = 294/560 - Subtract the two like fractions:
240/560 - 294/560 = 240 - 294/560 = -54/560 - After reducing the fraction, the answer is -27/280
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