what are they asking you for?
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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Answer: x=−3 or x=−5
Step-by-step explanation:
Step 1: Factor left side of equation.
(x+3)(x+5)=0
Step 2: Set factors equal to 0.
x+3=0 or x+5=0
x=−3 or x=−5
Answer:
Divisible by 3 is the answer
Step-by-step explanation:
First get everything to have the same base of 5
25^11 - 5^19
(5^2)^11 - 5^19
5^(2*11) - 5^19
5^22 - 5^19
Now factor out the GCF 5^19 to get
5^22 - 5^19
5^(19+3) - 5^(19+0)
5^19*5^3 - 5^19*5^0
5^19(5^3 - 5^0)
5^19(125 - 1)
5^19*(124)
At this point, we factor the 124 into 31*4 to end up with this full factorization: 5^19*31*4
Therefore, 25^11 - 5^19 is equivalent to 5^19*31*4
Since 31 is a factor of the original expression, this means the original expression is divisible by 31.
Answer:
Q (2.5, -4)
Step-by-step explanation:
Let A (1, -5), C = (10, 1), find Q (x, y), so that AQ:QC = 1:5
AQ = (x - 1, y + 5)
QC = (10 - x, 1 - y)
AQ:QC = 1:5
so 5*AQ = QC
5(x - 1) = (10 - x)
5(y + 5) = 1 - y
Solve them:
5x - 5 = 10 - x
6x = 15
x = 15/6 = 2.5
5y + 25 = 1 - y
6y = -24
y = -24/6 = -4
Then answer is Q (2.5, -4)