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.
D.miles
Because the grocery store should be a few miles from your home.
Answer:
71
so there's a right angle and 19° i added them and got 109°. and remember a triangle is 180° so i did 180-109
Answer:
3:2
Step-by-step explanation:
The ratio of boys to girls will be 12:8
But, this can be simplified, since both numbers are divisible by 4.
12/4 = 3
8/4 = 2
So, the simplified ratio of boys to girls is 3:2
The question is incomplete, here is the complete question:
The half-life of a certain radioactive substance is 46 days. There are 12.6 g present initially.
When will there be less than 1 g remaining?
<u>Answer:</u> The time required for a radioactive substance to remain less than 1 gram is 168.27 days.
<u>Step-by-step explanation:</u>
All radioactive decay processes follow first order reaction.
To calculate the rate constant by given half life of the reaction, we use the equation:
where,
= half life period of the reaction = 46 days
k = rate constant = ?
Putting values in above equation, we get:
The formula used to calculate the time period for a first order reaction follows:
where,
k = rate constant =
t = time period = ? days
a = initial concentration of the reactant = 12.6 g
a - x = concentration of reactant left after time 't' = 1 g
Putting values in above equation, we get:
Hence, the time required for a radioactive substance to remain less than 1 gram is 168.27 days.