The answer is A. You can get that in by plugging in and checking or by substitution. In order to use substitution here, you would plug in 3x + 3 into y in the first equation. You would then distribute the 2 and solve for x, which would give you 0. Then you could plug that into either equation to find that y = 3.
Answer:
Mean weight gained of two goods is not significantly different under 0.05 or 0.01 significance level, but it is under 0.10 significance level.
Step-by-step explanation:
We need to calculate the z-statistic of the differences of sample means and compare if it is significant under a significance level.
Z-score can be calculated using the formula:
z=
where
- X is the mean weight gain for in the first three months after birth for babies using the Gibbs products.
- Y is the mean weight gain for in the first three months after birth for babies using the competitor products
- s(x) is the population standard deviation of the sample for Gibbs brand
- s(y) is the population standard deviation of the sample for competitor brand
- N(x) is the sample size for babies used Gibbs product
- N(y) is the sample size for babies used competitor product.
putting the numbers in the formula:
z=
≈ -1.51
and z-table gives that P(z<-1.51) = 0.0655
To conclude if the competitor good is significantly better, we need to choose a significance level and compare it to 0.0655.
For example, the difference in mean weight gained of two goods is not significant under 0.05 or 0.01 significance since 0.0655 is bigger than these values. But we can conclude that under 0.10 significance, competitor brand mean weight gain is significantly more than the Gibbs brand mean weight gain.
What are you even supposed to do
Answer:
C. Stratified Sampling
Step-by-step explanation:
Stratified sampling is a sampling method in which the overall population is divided into a number of smaller sub groups.
These smaller sub-groups are called as strata.
These sub-groups are formed on the basis of similar characteristics and attributes shared by the population.
It is also known as proportional random sampling.
Answer:
280.8997
Step-by-step explanation:
cross section = 2*15*5+2*(25/360)*15*15*pi+5*(25/360)*2*pi*15
= 280.8997