Answer:
28.6, that is, about 29 are expected to be defective
Step-by-step explanation:
For each battery, there are only two possible outcomes. Either it is defective, or it is not. The probability of a battery being defective is independent of other betteries. So the binomial probability distribution is used to solve this question.
Binomial probability distribution
Probability of exactly x sucesses on n repeated trials, with p probability.
The expected value of the binomial distribution is:

The probability that a battery is defective is 1/14.
This means that 
400 batteries.
This means that 
How many are expected to be defective?

28.6, that is, about 29 are expected to be defective
Answer:
Step-by-step explanation:
Let's begin the solution by isolating the 4x term:
4x- c= k => 4x = c + k
Now divide both sides by 4:
c + k
x = --------------
4
This does not match Answer C, but would match Answer C if k + c were divided by 4. Answer C, as shown, is incorrect.
Answer:
Adults=8
Childrens=2
Seniors=2
Step-by-step explanation:
Children $4
Adults $6
Seniors $5
There are an equal number of seniors and children.
The entire group spent a total of $66.
If 11 adults attended, the total amount will be $66 and the number of senior and childrens will be the same, 0. But this is not possible because the statement says that childrens and seniors are part of the group.
If we add the charges of childrens and seniors is equal to $9.
Assuming that the group has 2 childrens and 2 seniors the add is equal to:
Now we substract the result from the total amount:

48 is multiple of 6, this means we have in the group 8 adults, 2 childrens and 2 seniors.
Well its 1 and 5 tenths
- 1.5 = 15 tenths
- 5 groups of 3 is the answer
because 5 x 3 = 15
The polygon in option 3 is not octagon at all, it is heptagon (or 7-sided polygon).
A convex octagon has no angles pointing inwards. More precisely, no internal angles can be more than 180°.
When some internal angle is greater than 180°, it is concave.
In option 2 you can see that one angle is pointing inward, then this octagon is concave.
Answer: correct choice is B.