A change in any one of the underlying factors that determine what quantity people are willing to buy at a given price will cause a shift in demand. Graphically, the new demand curve lies either to the right (an increase) or to the left (a decrease) of the original demand curve.
So the ratios are 5:5 and 3:5 so the fractions are 5/10 (1/2) for 7th grade and 5/8 for 8th grade
We conclude that the sum of the first 8 terms of the arithmetic sequence is 17/5.
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How to get the sum of the first 8 terms?</h3>
In an arithmetic sequence, the difference between any two consecutive terms is a constant.
Here we know that:

There are 7 times the common difference between these two values, so if d is the common difference:

Then the sum of the first 8 terms is given by:

So we conclude that the sum of the first 8 terms of the arithmetic sequence is 17/5.
If you want to learn more about arithmetic sequences:
brainly.com/question/6561461
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