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!
Answer:
C) senior citizen ticket 10$, child ticket 11$
Step-by-step explanation:
Answer:
[A] (4 ÷ 2)+(0.8 ÷ 2)
Step-by-step explanation:
Divide the 2 into each digit, which must be in the same spot it was before:
Knowing that 8 in 4.8 ⇒ 0.8
Thus, you can infer that [B] is wrong
You also infer that [D] and [C] is wrong because 4 is a whole number.
Thus, that left us with [A] 4 ÷ 2+0.8 ÷ 2 which shows the quotient of 4.8 ÷ 2
Hence, [A] 4 ÷ 2+0.8 ÷ 2 is the answer.
<em>~Learn with Lenvy~</em>
The total number of produced details increased by 6.4%
suppose the starting number was x.
suppose x=100
100 +12%= 112
112-5%=106.4
106.4-100=6.4
6.4%
<span>The speed v of a gear varies inversely as the number of teeth t
</span>
if a gear that has 42 teeth makes 24 revolutions per minute
<span> Then a gear that has 24 teeth will make 42 revolutions.
Hope it helps!
</span>
