Emi computes the mean and variance for the population data set 87, 46, 90, 78, and 89. she finds the mean is 78. her steps for finding the variance are shown below.

the answer would be the third choice, she put the negative sign for the 32 outside the parenthesis

Step-by-step explanation:

Answer with explanation:

The Given data set having 5 variate arranged in ascending order = {46,78,87,89,90}

Mean of a data set

Mean of the given data set

→Emi has calculated the mean Correctly which is 78.

Now to calculate variance

1. Square of  Absolute difference between mean and each variate

a. | 78-46|²=32² =1024

b. | 78 - 78 |²=0²=0

c. | 89-78|²=11²=121

d. | 87-78 |²=9²=81

e. | 90-78|²=12²=144

The new data set obtained is ={ 0,81,121,144,1024}

Variance    

Variance = 342.5  

.25

step-by-step explanation:

3

step-by-step explanation:

in standard form:

a= dictionaries

b= maps

you have to buy 3 dictionaries, so put a 3 next to the a (dictionaries) so that you can multiply them by each other.

a3+b= 60 (the amount of money you have)

we already know the cost of a=15 so replace a with $15

($15 x 3)+b=60

multiply 15 and 3 to get $45 and replace it with $45

45+b=60

and then replace b with 15 to get the total:

45+15=60

that means you have $15 left after buying 3 dictionaries.

15 divided by the cost of a map ($5) equals 3.

so you can buy 3 maps.

sorry if it was confusing!