Subtract 20/70 from 12/45
12/45 - 20/70 is -2/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
12/45 = 12 × 14/45 × 14 = 168/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
20/70 = 20 × 9/70 × 9 = 180/630 - Subtract the two like fractions:
168/630 - 180/630 = 168 - 180/630 = -12/630 - After reducing the fraction, the answer is -2/105
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