<PRE><B>Question 352191</B>
Hi,
*Note: The probability of x successes in n trials is: 
.
P = nCx* {{{p^x}}}*{{{q^(n-x)}}} where p and q are the probabilities of success and failure respectively. 
.
nCx = {{{n!/(x!(n-x)!)}}}
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Question states p(dog drawn) = 10/25 0r .4  and q (cat drawn) = .6
.

Probability (At least 1 cat) =  1 - P(no cats)
P(no cats)
7C7 = {{{ 7!/(7!*0!)!= 1 }}}
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P(no cats) = {{{1*(.4)^7*(.6)^0}}} = .0016
.
1 - P(no cats) = .9983</PRE>