Answer:
If our random variable of interest for this case is X="the number of teenagers between 12-17 with smartphone" we can model the variable with this distribution:

And the mean for this case would be:

And the standard deviation would be given by:

Step-by-step explanation:
If our random variable of interest for this case is X="the number of teenagers between 12-17 with smartphone" we can model the variable with this distribution:

And the mean for this case would be:

And the standard deviation would be given by:

Answer:
1,961.6
Step-by-step explanation:
Answer:

Step-by-step explanation:
If there are 9 marbles in total and the desired outcome is to pick a green marble then the probability is
=
which simplifies down to a third.
Hello! For these kinds of problems, the formula for finding the principal is I / rt. That means, divide the simple interest by the rate and time (rate should be in decimal form). In order to find simple interest, just do prt, which means multiply the principal (initial amount) by the rate (simple interest rate, in decimal form) by the amount of time (could be in months or years). With that being said, if you solve it correctly, here are your answers:
Principal: $14,181
Interest rate: 10%
Time: 4 years
Simple Interest: $5,672.40
Principal: $83,079
Interest rate: 9%
Time: 2 years
Simple Interest: $14,954.22
Principal: $659,379.96
Interest rate: 11.7%
Time: 28 months
Simple Interest: $179,753.57
Principal: $18,936
Interest Rate: 2.41%
Time: 3 Months
Simple Interest: $114.09
Note: If the time is in months, be sure to convert it into a decimal and multiply. If a decimal repeats, just convert it to the nearest hundredth.