A standard deviation of 10 values is 8.19. You add 5 points to each score in the sample. The standard deviation for the new sample is:

a. Grand Mean = 2.799

b. Standard Deviation = 0.01387

c. Standard Error = 0.0016

d. The range with a Z score of 3 = (2.75739, 2.84061)

Step-by-step explanation:

a. Grand mean :

Given that

Sum of 80 values = 223.91

Total observation = 80

Grand mean = 223.91/80 = 2.799

b. With the excel command "STDEV[range of cells]", we get the standard deviation as = 0.01387

c. Standard error =  Standard deviation / root of n

d. The range with a Z score of 3 :

lower limit = mean - (3 * SD) = 2.799 - (0.04161) = 2.75739

upper limit = mean + (3 * SD) = 2.799 + (0.04161) = 2.84061

a. Grand Mean = 2.799

b. Standard Deviation = 0.01387

c. Standard Error = 0.0016

d. The range with a Z score of 3 = (2.75739, 2.84061)

Step-by-step explanation:

a. Grand mean :

Given that

Sum of 80 values = 223.91

Total observation = 80

Grand mean = 223.91/80 = 2.799

b. With the excel command "STDEV[range of cells]", we get the standard deviation as = 0.01387

c. Standard error =  Standard deviation / root of n

d. The range with a Z score of 3 :

lower limit = mean - (3 * SD) = 2.799 - (0.04161) = 2.75739

upper limit = mean + (3 * SD) = 2.799 + (0.04161) = 2.84061

SI=(P*R*T)/100

P=2000

R=1.5

T=6

SI=(2000*1.5*6)/100

=(2000*9)/100

=180

Neil will earn interest of 180

For every 8 cars there are 7 trucks

Therefore,

Cars:Truck=8:7

Answer is B)8:7

F=ma

where F=force

m=mass

a=acceleration

Here,

F=4300

a=3.3m/s2

m=F/a

    =4300/3.3

    =1303.03kg

Salesperson will make 6% of 1800

=(6/100)*1800

=108

Salesperson will make $108 in $1800 sales

The answer is in the image 

Here,

tip=18%of $32

tip=(18/100)*32

=0.18*32

=$5.76

Total payment=32+5.76=$37.76