We can say that there are 20 blueberry muffins for every 15 bran muffins, according to the given information. This can be expressed as 20:15 in ratio form. We can simplify this ratio further, by dividing both sides by 5, to leave us with the simplified ratio of blueberry to bran muffins, 4:3
Answer:
This sampling technique is called cluster
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:
The population is divided into groups(by stores), and all elements of the groups(all customers at the stores are sampled), which is the characteristic of a cluster sampling.
Find the soluiton
2x+2y=16
3x-y=4
x+y=8
<u>3x-y=4+</u>
4x=12
x=3
3(3)-y=4
9-y=4
y=5
(3,5)
test them to see if get true statment
obviously the first equatons of 1,2,4 work
1 doesn't work
2, works
4. doesn't work
2 is the same as the first except both euations are just doubled
answer is 2
If you have at least as many equations as your have unknown variables, the 'system' is solvable (unless the equations are copies of eachother).
In this case, isolate one letter and plug it in the other. I'm going for the 2a in the bottom one (it doesn't matter)
2a - 4b = 12 => (divide by two and move the b's to the other side)
a = 6 + 2b. (plug this one into the top equation)
4(6+2b) + 6b = 10 => 24+8b+6b = 10 => 24 + 14b = 10 => 14b = -14 => b=-1
a = 6 + -2 = 4.
So a=4 and b=-1.
