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2 years ago

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What is the nth term rule of the quadratic sequence below? 7, 14, 23, 34, 47, 62, 79 Please could someone help me and write a st

ep by step explanation? Thanks :D

1 answer:

belka [17]2 years ago

5 0

Step-by-step explanation:

The first differences are 7,9,11,13,15,17 and the second differences are 2.

This means that the first term of the sequence is n^2.

Subtracting n^2 from the sequence gives 6,10,14,18,22,26, which has nth term of 4n + 2.

So putting these together gives a nth term of the quadratic sequence of n^2 + 4n + 2.

Hope it helped and tell me if I went wrong :)

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$Range = 16$

$Inter\ Quartile\ Range = 6.75$

$Variance = 20.44$

$Standard\ Deviation = 4.52$

Step-by-step explanation:

Given

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From the given data;

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Inter quartile range (IQR) is calculates as thus

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Where

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<em />

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1, 3, 4, 5, 6, 9, 9, 10, 12, 17

N = Number of data; N = 10

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Calculating Q3

$Q_3 = \frac{3}{4}(N+1) th\ item$

<em>Substitute 10 for N</em>

$Q_3 = \frac{3}{4}(10+1) th\ item$

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$Q_3 = \frac{33}{4} th\ item$

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Express 8.25 as 8 + 0.25

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Express 0.25 as fraction

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Calculating Q1

$Q_1 = \frac{1}{4}(N+1) th\ item$

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$Q_1 = \frac{1}{4}(10+1) th\ item$

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