Current research indicates that the distribution of the life expectancies of a certain protozoan is normal with a mean of 49 days and a standard deviation of 10.2 days. Find the probability that a simple random sample of 64 protozoa will have a mean life expectancy of 54 or more days.

The probability that a simple random sample of 64 protozoa will have a mean life expectancy of 54 or more days is P(M>54)=0.00004.

Step-by-step explanation:

In this case, we have a population lifetime normally distributed with mean 49 and standard deviation 10.2.

We take a sample of size n=64.

Then, we can calculate the z-score for a sample mean M=54, in order to calculate P(M>54):

The probability that a simple random sample of 64 protozoa will have a mean life expectancy of 54 or more days is P(M>54)=0.00004.

-2

7 - 9 = -2

reversed:

-2 + 9 = 7

step-by-step explanation:

given perimeter: 28cm

length: 9cm

atp,

2(l+w)=p of the reactangle

2(9+x)=28

18+2x=28

2x=28-18

x=10/2

x=5

therefore width is 5 cm