Each question has four choices, then the probability to guess a correct answer is

and the probability to select incorrect choice is

.
You have a 5-question multiple-choice test, then n=5. The <span>probability that you will guess exactly three out of five questions correctly is </span>
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</span><span>

</span>

.
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( x + 1 )/ 3 = x + 2
Multiply 3 on both sides
x + 1 = 3x + 6
Subtract 6 on both sides
x - 5 = 3x
Subtract x from both sides
-5 = 2x
Divide 2 from both sides
x = -2.5
2x^2-7x-4=0
2x^2-8x+x-4=0
2x(x-4)+1(x-4)=0
(2x+1)(x-4)=0
x=-1/2, 4
Answer:
12
Step-by-step explanation:
144 divided by 2 72
72 by 2 36
36 by 2 18
18 by 2 9
3by 3 3
3 by3 1
2x2 2x2 2x2 3x3
pick on from each set
2x2x3
12