Bunuel wrote:
If\(S\) is the set of all fractions defined by the formula\(\frac{n}{n+1}\) , where\(n\) is a positive integer less than 20, what is the product of all the fractions that are in\(S\) ?
A. \(\frac{1}{20}\)
B. \(\frac{1}{21}\)
C. \(\frac{1}{2}\)
D. \(\frac{19}{40}\)
E. \(\frac{19}{20}\)
Just try it in your head.
1/2 * 2/3 * 3/4 *...... * 19/20
(Be careful. n is less than 20 so max is 19 so the last fraction is 19/20)
Everything but 1/20 cancels out.
Answer A
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