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2 years ago

8z + 15 = -1 | z = ?

Mathematics

1 answer:

Fiesta28 [93]2 years ago

6 0

Answer:

z = -2

Step-by-step explanation:

Step 1: Write equation

8z + 15 = -1

Step 2: Solve for <em>z</em>

Subtract 15 on both sides: 8z = -16
Divide both sides by 8: z = -2

Step 3: Check

<em>Plug in z to verify it's a solution.</em>

8(-2) + 15 = -1

-16 + 15 = -1

-1 = -1

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Step-by-step explanation:

The confidence interval for population mean(when population standard deviation is unknown) is given by :-

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