Answer:
0.0111% probability that he answers at least 10 questions correctly
Step-by-step explanation:
For each question, there are only two outcomes. Either it is answered correctly, or it is not. The probability of a question being answered correctly is independent from other questions. So we use the binomial probability distribution 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.
A multiple-choice examination has 15 questions, each with five answers, only one of which is correct.
This means that 
What is the probability that he answers at least 10 questions correctly?









0.0111% probability that he answers at least 10 questions correctly
Answer:
1 hour and 40 minutes
Step-by-step explanation:
im high asfff
For the first digit you are choosing from 2 digits
for the second digit you are choosing from 2 digits
for the third digit you are choosing from 2 digits
2*2*2=8
111
110
011
101
000
001
100
010
However......
A number doesn't usually start with a 0 or 0s.
Therefore, if you want 3-digit numbers and not just permutations using 0 and 1, then you must eliminate
011, 000, 001, and 010
Seeing that the first digit can't be 0, you choose from 1, then 2, and then 2 digits again; 1*2*2=4 numbers
You choose which answer best suits your problem.
Answer: The lamppost is 7 feet 2 inches
Step-by-step explanation: If Ann measured her own height and her shadow, then what she used is a ratio between both measurements. If she can measure the shadow of the lamppost, then she can use the same ratio of her height and it’s shadow to derive the correct measurement of the lamppost.
If Ann’s height was measured as 5 feet 3 inches, and her shadow was 8 feet 9 inches, the ratio between them can be expressed as 3:5.
Reduce both dimensions to the same unit, that is, inches. (Remember 12 inches = 1 foot)
Ratio = 63/105
Reduce to the least fraction
Ratio = 3/5
If the height of the lamppost is H, then
H/144 = 3/5
H = (144 x3)/5
H = 86.4
Therefore the lamppost is approximately 86 inches, that is 7 feet and 2 inches tall.
The range would be the difference between the lowest age and the highest age.
The highest age is 76, the lowest age is 30
The range is 76 - 30 = 46