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mr Goodwill [35]
2 years ago
9

In an arithmetic sequence, the sum of the first n terms is s_n=n^2. find a_8

Mathematics
1 answer:
Julli [10]2 years ago
4 0

Answer:

a_{8}  = 15

Step-by-step explanation:

a_{1} + a_{2} + ..... + a_{7} + a_{8} = 8^{2} = 64

-a_{1} - a_{2} ..... - a_{7} = - 7^{2} = -49    Now add the two equations

                                 a_{8} = 64 - 49 = 15

a_{8}  = 15

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In a survey, 24 people were asked how much they spent on their child's last birthday gift. The results were roughly bell-shaped
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The 98% confidence interval for the mean amount spent on their child's last birthday gift is between $40.98 and $43.02.

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We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.

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98% confidence interval

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