The answer to w<span>hat is the value of a in the expression 7 to the power of d = of 3 square root of 7 is a=19.</span>
Answer:
Stratified sampling
Step-by-step explanation:
Samples may be classified as:
Convenient: Sample drawn from a conveniently available pool.
Random: Basically, put all the options into a hat and drawn some of them.
Systematic: Every kth element is taken. For example, you want to survey something on the street, you interview every 5th person, for example.
Cluster: Divides population into groups, called clusters, and each element in the cluster is surveyed.
Stratified: Also divides the population into groups. However, then only some elements of the group are surveyed.
In this question:
Population divided into groups, and random samples are drawn from the groups. This is a mark of stratified sampling.
To solve this problem you must apply the proccedure shown below:
1. She has a total of 50 DVDs of 90 minutes each one of them. The cost of each DVD was 11€.
2. Therefore, to calculate the total cost of the collection, you must multiply the cost of each DVD by the total number of them:
€
3. To calculate the total minutes of the collection, you must multiply 90 minutes by the total number of DVDs:

Therefore, the answer is: 550€ and 4500 minutes.
Answer:
x = -11/5 and y = 24/5
Step-by-step explanation:
Use elimination.
First, we need to multiply so that at least one variable can cancel out.
We can multiply the top equation by 2.
So we get
4x + 6y = 20
Then, we can use elimination.
The x's cancel out.
So we get 5y = 24
Or y = 24/5
Then, we can plug in this y value back into the first equation to find x.
2x + 3(24/5) = 10
2x + 72/5 = 50/5
2x = -22/5
x = -11/5
So x = -11/5 and y = 24/5