Answer: 225 students would have at least one sibling.
Step-by-step explanation:
Three out of four is the same as 3/4 meaning that if there are 300 students in your school then 3/4 times 300 will give the number of students with at least one sibling.
3/4 * 300 = 225
This means 225 students would have at least one sibling.
Answer:
24 quarters and 49 nickels
Step-by-step explanation:
This situation has two unknowns - the total number of nickels and the total number of quarters. Because we have two unknowns, we will write a system of equations with two equations using the two unknowns.
- n+q=73 is an equation representing the total number of coins
- 0.05n+0.25q=8.45 is an equation representing the total value in money based on the number of coin. 0.05 and 0.25 come from the value of a nickel and quarter individually.
We write the first equation in terms of q by subtracting it across the equal sign to get n=73-q. We now substitute this for n in the second equation.
0.05(73-q)+0.25q=8.45
3.65-0.05q+0.25q=8.45
3.65+0.20q=8.45
After simplifying, we subtract 3.65 across and divide by the coefficient of q.
0.20q=4.8
q=24
We now know of the 73 coins that 24 are quarters. To find the number of nickels, we subtract 24 from 73 and get 49 nickels.
Answer:
0.5981 = 59.81% probability that three or less of the selected adults have saved nothing for retirement
Step-by-step explanation:
For each adult, there are only two possible outcomes. Either they save nothing for retirement, or they save something. The probability of an adult saving nothing for retirement is independent of any other adult. This 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.
20% of adults in the United States save nothing for retirement (CNBC website).
This means that 
Suppose that sixteen adults in the United States are selected randomly.
This means that 
What is the probability that three or less of the selected adults have saved nothing for retirement?
This is:

In which






0.5981 = 59.81% probability that three or less of the selected adults have saved nothing for retirement
Scientific notation means the numbers have to be between 1 and 10, so here is the answer as well as where to move the decimal