To solve this problem, we should note that there are:
total questions = 100
questions answered correctly = 90
questions that needed additional clues = 10
1. The first question is to find the probability that in the
third question, Mary would need additional clue. Therefore this implies that in
the first and second questions, Mary would answer it correctly. Therefore:
Probability = (question 1 answered correctly) * (question 2 answered
correctly) * (question 3 needed clue)
Probability = (90/100)*(89/99)*(10/98)
Probability = 0.08256 = 8.26%
2. The second question finds for the probability that two
consecutive needs additional clue, therefore:
Probability = (question 1 needed clue) * (question 2 needed
clue)
Probability = (10/100)*(9/99)
Probability = 9.1*10^-3 = 0.91%
Answer:
x = 10 cm, y = 5 cm gives a minimum area of 300 cm^2.
Step-by-step explanation:
V= x^2y = 500
Surface area A = x^2 + 4xy.
From the first equation y = 500/x^2
So substituting for y in the equation for the surface area:
A = x^2 + 4x * 500/x^2
A = x^2 + 2000/x
Finding the derivative:
dA/dx = 2x - 2000x^-2
dA/dx = 2x - 2000/x^2
This = 0 for a minimum/maximum value of A, so
2x - 2000/x^2 = 0
2x^3 - 2000 = 0
x^3 = 2000/ 2 = 1000
x = 10
Second derivative is 2 + 4000/x^3
when x = 10 this is positive so x = 10 gives a minimum value of A.
So y = 500/x^2
= 500/100
= 5.
Answer:
see explanation
Step-by-step explanation:
the equation of a circle in standard form is
(x - h)² + (y - k)² = r²
where (h, k) are the coordinates of the centre and r is the radius
To obtain this form use the method of completing the square on both the x and y terms
rearranging
x² + 6x + y² - 4y = 12
x² + 2(3)x + 9 + y² + 2(- 2)y + 4 = 12 + 9 + 4
(x + 3)² + (y - 2)² = 25 ← in standard form
with centre = (- 3, 2) and r = 
= 5
Answer:
$67
Step-by-step explanation:
one hundred percent means the whole value
