Answer:
a) 8*88*10⁻⁶ ( 0.00088 %)
b) 0.2137 (21.37%)
Step-by-step explanation:
if the test contains 25 questions and each questions is independent of the others, then the random variable X= answer "x" questions correctly , has a binomial probability distribution. Then
P(X=x)= n!/((n-x)!*x!)*p^x*(1-p)^(n-x)
where
n= total number of questions= 25
p= probability of getting a question right = 1/4
then
a) P(x=n) = p^n = (1/4)²⁵ = 8*88*10⁻⁶ ( 0.00088 %)
b) P(x<5)= F(5)
where F(x) is the cumulative binomial probability distribution- Then from tables
P(x<5)= F(5)= 0.2137 (21.37%)
Answer:
47.5%
Step-by-step explanation:
You have to first subtract 80 and 42 to find the decrease first. This is 38. Now, you have to divide this by the original number which is 80. So 38 divided by 80 is 0.475.
Now multiply this by 100.
You can easily move the decimal point to the right.
So you would get 47.5%
Hope this helped!
Answer:
D
Step-by-step explanation:
Given the 2 equations
y = x - 5 → (1)
y = x² - 5x + 3 → (2)
Substitute y = x² - 5x + 3 into (1)
x² - 5x + 3 = x - 5 ← subtract x - 5 from both sides
x² - 6x + 8 = 0 ← in standard form
(x - 2)(x - 4) = 0 ← in factored form
Equate each factor to zero and solve for x
x - 2 = 0 ⇒ x = 2
x - 4 = 0 ⇒ x = 4
Substitute each of these values into (1) for corresponding values of y
x = 2 → y = 2 - 5 = - 3 ⇒ (2, - 3 )
x = 4 → y = 4 - 5 = - 1 ⇒ (4, - 1 )
Ok question is there numbers with this
