Answer:
Step-by-step explanation:
Hello!
The variable of interest is:
X: number of daily text messages a high school girl sends.
This variable has a population standard deviation of 20 text messages.
A sample of 50 high school girls is taken.
The is no information about the variable distribution, but since the sample is large enough, n ≥ 30, you can apply the Central Limit Theorem and approximate the distribution of the sample mean to normal:
X[bar]≈N(μ;δ²/n)
This way you can use an approximation of the standard normal to calculate the asked probabilities of the sample mean of daily text messages of high school girls:
Z=(X[bar]-μ)/(δ/√n)≈ N(0;1)
a.
P(X[bar]<95) = P(Z<(95-100)/(20/√50))= P(Z<-1.77)= 0.03836
b.
P(95≤X[bar]≤105)= P(X[bar]≤105)-P(X[bar]≤95)
P(Z≤(105-100)/(20/√50))-P(Z≤(95-100)/(20/√50))= P(Z≤1.77)-P(Z≤-1.77)= 0.96164-0.03836= 0.92328
I hope you have a SUPER day!
Using Pythagorean, a^2 + b^2 = c^2
16 +x^2 = 36.69
Then subtract the 16 from 36.69, which is 23.69
And finally take the square root of that, giving you 4.87
It's a coffin because the person who makes it is alive so they don't need to use it, the person who buys it is also alive and buying it for someone else.
The person who is using it has passed away so they can't see or feel anything.
:( This is one morbid riddle.
It would be 20.4 km because if 1cm is 12km then you just have to multiply 1.7 x 12 = 20.4.
12 per hour
24 2 hours
36 3 hours
Closest answer would be (A) Im 100% Sure!!!
