document.write( "Question 1114092: b) The Weather Office forecasts the probability of a rainfall the next day as forty-two percent. What is the probability that it will not rain?
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\n" ); document.write( "c) Which of the followings are not probabilities?\r
\n" ); document.write( "\n" ); document.write( "a) 0.005
\n" ); document.write( "b) 1.02
\n" ); document.write( "c) ¼
\n" ); document.write( "d) 101%
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\n" ); document.write( "\n" ); document.write( "d) A box contains 5 blue, 7 red and 8 yellow balls. A ball is drawn at random. What is the probability that the ball drawn is not yellow? (2 marks)\r
\n" ); document.write( "\n" ); document.write( "e) How many blue balls have to be added to the box to increase the probability of picking a blue ball at random to 50%?\r
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Algebra.Com's Answer #729110 by Fombitz(32388)\"\" \"About 
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b) It must either rain or not rain so,
\n" ); document.write( "\"P%5BNR%5D%2B0.42=1\"
\n" ); document.write( "\"P%5BNR%5D=1-0.42\"
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\n" ); document.write( "c) Probability must a number between 0 and 1.
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\n" ); document.write( "d) Find the probability that the ball is yellow.
\n" ); document.write( "\"P%28Y%29=8%2F%285%2B7%2B8%29=8%2F20=2%2F5\"
\n" ); document.write( "So the complement would be the probability of not yellow.
\n" ); document.write( "\"P%28NY%29=1-2%2F5\"
\n" ); document.write( "\"P%28NY%29=3%2F5\"
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\n" ); document.write( "e) \"P%28B%29=1%2F2\"
\n" ); document.write( "Let the number of blue balls added be equal to X,
\n" ); document.write( "\"%285%2BX%29%2F%2820%2BX%29=1%2F2\"
\n" ); document.write( "\"2%285%2BX%29=1%2820%2BX%29\"
\n" ); document.write( "\"10%2B2X=20%2BX\"
\n" ); document.write( "\"X=20-10\"
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