18=p+d+n, 3p=d, 2n=d
The lowest number that is divisible by 3&2 is 6 so, there is 6 nickels.
There is 6 nickels and there is half of that in dimes, 3 dimes.
There is three times the amount of pennies of dimes. 3*3=9. There is 9 pennies.
6 nickels + 3 dimes + 9 pennies= 18 coins
Density=m/V
m=80 gr
V=200cm^3
Density=80gr/200cm^3
Density=0.4 gr per cubic centimeter
Answer:
232
Step-by-step explanation:
The second one would be the answer. You want to plug in for this question. You can divide over the five leaving you with (x-2)^2 =25. Since you are squaring this answer, you want to get either 5 or negative five. Both -3 and 7 will do that.
Answer:
The 90% confidence interval for the mean test score is between 77.29 and 85.71.
Step-by-step explanation:
We have the standard deviation for the sample, so we use the t-distribution to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 25 - 1 = 24
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 24 degrees of freedom(y-axis) and a confidence level of
. So we have T = 2.064
The margin of error is:

In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 81.5 - 4.21 = 77.29
The upper end of the interval is the sample mean added to M. So it is 81.5 + 4.21 = 85.71.
The 90% confidence interval for the mean test score is between 77.29 and 85.71.