Answer:
a) The expected number of questions that are answered correctly by both A and B = 11 (7 + 4).
b) The Variance of the number of questions that are answered correctly by either A or B = 2.25.
Step-by-step explanation:
Number of questions in the examination = 10
Probability of A's answer being correct = 0.7
Probability of B's answer being correct = 0.4
The expected number of questions that are answered correctly by both A and B:
Probability of Expected
Correct Answer Value Variance
A 0.7 7 (0.7 * 10) 2.25
B 0.4 4 (0.4 * 10) 2.25
Total expected value = 11
Mean = 5.5 2.25
I hope choices must be given in the problem.
I am showing the method to find the equivalent equation of the above equation. You can match with your given choices.
First step is to expand the first term. So,
(x-4)² = (x - 4)(x - 4) Since a²= a*a
= x² - 4x - 4x + 4 * 4 By multiplying.
= x² -8x + 16 Combine the like terms.
So, (x - 4)² - (x -4) - 6
= x² - 8x + 16 - x + 4 - 6
= x² - 9x + 14 Combine the like terms.
So, equivalent equation of the above equation is x² - 9x + 14 = 0.
Answer:
C
Step-by-step explanation:
It would be -12 to go to the last cube so u subtract 12 from every number then multiply the numbers
The formula for the area of a parallelogram is base times height or bh.
There's a formula sheet on Khan Academy:
https://www.khanacademy.org/math/basic-geo/basic-geo-area-and-perimeter/parallelogram-area/a/area-of...
Answer: OPTION D.
Step-by-step explanation:
You know that Lindy's total cost can be found using this expression provided in the exercise:

Where "d" is the number of drinks she orders and "t" is the number of toppings for a medium pizza she orders.
Since she and her friends to order 4 drinks and a medium pizza with 3 toppings, you can find the total cost by substitute values into the given expression.
The values are:

Substituting into the expression and evaluating, you get:
