Answer:
0.2611 = 26.11% probability that exactly 2 calculators are defective.
Step-by-step explanation:
For each calculator, there are only two possible outcomes. Either it is defective, or it is not. The probability of a calculator being defective is independent of any other calculator, which means that the binomial probability distribution is used to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.
And p is the probability of X happening.
5% of calculators coming out of the production lines have a defect.
This means that 
Fifty calculators are randomly selected from the production line and tested for defects.
This means that 
What is the probability that exactly 2 calculators are defective?
This is P(X = 2). So


0.2611 = 26.11% probability that exactly 2 calculators are defective.
Your answer is B. 2
This is because to rationalise the denominator, we need to multiply it by (3 - √7), so we get:
(3 + √7)(3 - √7)
3 × 3 = 9
3 × √7 = 3√7
3 × -√7 = -3√7
√7 × -√7 = -7
So all in all you get 9 - 7 which is 2.
I hope this helps!
Answer:
ANSWER
y = 3x + 6.50
EXPLANATION
The $3 for each downloaded movie is the unit rate of change.
This is represent the slope of the linear function that models this situation.
The monthly fee of monthly fee of $6.50 the constant rate.
It represents the y-intercept of the function.
The linear function is given by
y = mx + by=mx+b
The correct choice is y = 3x + 6.50