Sin+cos=90
49+cos=90
cos=41
Answer: -5
Step-by-step explanation: The common difference is the same number we are adding each time to get from one term to the next.
In this sequence, we are adding -5 each time
so our common difference is -5.
The sample used in this problem is classified as cluster.
<h3>How are samples classified?</h3>
Samples may be classified as:
- Convenient: Drawn from a conveniently available pool.
- Random: All the options into a hat and drawn some of them.
- Systematic: Every kth element is taken.
- Cluster: Divides population into groups, called clusters, and each element in the cluster is surveyed.
- Stratified: Also divides the population into groups. Then, a equal proportion of each group is surveyed.
For this problem, a group of schools is selected, and then the new program is applied to all students in these school, meaning that all elements in the cluster are surveyed, so cluster sampling is used.
More can be learned about classification of samples at brainly.com/question/25122507
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Answer:
y = 1.5x + 3.2009
Step-by-step explanation:
I plotted your points and drew a linear regression line.
Its equation is
y = 1.5x + 3.2009
The regression line ignores the fact that the points fall along a smooth curve.
A parabolic regression line fits the data much better.
The equation for that line is
y = - 0.1647x² + 4.1357x - 5.6946
It is the equation for a vertical parabola opening downward.
