Subtract 20/70 from 12/18
12/18 - 20/70 is 8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 18 × 35 = 630,
12/18 = 12 × 35/18 × 35 = 420/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
20/70 = 20 × 9/70 × 9 = 180/630 - Subtract the two like fractions:
420/630 - 180/630 = 420 - 180/630 = 240/630 - After reducing the fraction, the answer is 8/21
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