Find the z score of A time for the 100 meter sprint of 20.0 seconds at a school where the mean time for the 100 meter sprint is 17.7 seconds and the standard deviation is 2.1 seconds

z = 1.095

Step-by-step explanation:

To calculate the value of z, it is to replace in the corresponding formula:

z = (x - m) / sd

where m, which is the mean, which has the value of 17.7

x, the sample, which would be 20

and sd the standard deviation, which is equal to 2.1

Now by replacing all the values:

z = (20 - 17.7) /2.1

z = 1.095

the answer is c

step-by-step explanation:

341

step-by-step explanation:

all you have to do is 9x31 (which equals 279) and then 20x31 (which equals 620). then you have to subtract. 620-279=341.