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.
The answer is b. It is the only choice that equals the right answer. You could also write this as 3 * 10^4, which is equivalent to b.
Answer: No, it would be 2/5.
Step-by-step explanation: 2 1/4 - 6/7 is equal to about 1.4 when rounded to the nearest tenth. 1.4 as a fraction would be 4/10. 4/10 is simplified to 2/5 by dividing each number by 2.
Answer:
A
Step-by-step explanation:
Number times landing on green) = 150 * 1/5 = 30
Number times landing on yellow = 150 * 1/5 = 30
Answer 60 times