Answer:
The probability is 0.28157
Step-by-step explanation:
The number of answers are 40 answers ( 10 questions and 4 answer each)
The number of correct answers is only 10
So the probability that he answers 2 exactly out of 10 means he correctly selected 2 answers
The probability will be;
10 C 2/ 40 C 10
This mean out of the total 10 correct, he selects 2 and out of the total 40 , he selects 10
The probability of selecting a correct answer is;
1/4 while the probability of selecting a wrong one is 3/4
So probability of selecting 2 correct out of a total 10 will be
10 C 2 (1/4)^2 (3/4)^8
= 0.28157
Answer:
x = 9
Step-by-step explanation:
First, we want to isolate variable x on the left side of the equation. We can do this by adding 13 to both sides.
x - 13 + 13 = - 4 + 13
x = 9
The current depth of the hole is at least 20 feet below ground level.
Inequality is an expression that shows the non equal comparison of numbers and variables.
Let d represent the current depth of the hole.
To be at least 40 feet below ground level, he need more than 2 times its current depth.
2d < -40
d < -20
Hence the current depth of the hole is at least 20 feet below ground level.
Find out more on inequalities at: brainly.com/question/11613554
Answer:
Step-by-step explanation:
let be x the price before the discount
original price= 28/(1-0.25)=28/0.75=37.33
original price=37.33
28.8 = 18x....divide both sides by 18, eliminating the 18 on the right side
28.8 / 18 = x
1.6 = x <==