Question

Hi, can you help me answer this question please, thank you!

Answer 1

we will use the following formula to find the Z value

`Z=\frac{x-\mu}{\frac{\sigma}{\sqrt[]{n}}}`

where,

x : sample mean = 26.7

μ : mean of expectation = 27.99

σ : standard deviation = 4.02, and

n : sample = 45

therefore:

`Z=\frac{x-\mu}{\frac{\sigma}{\sqrt[]{n}}}=\frac{26.7-27.99}{\frac{4.02}{\sqrt[]{45}}}`

solving this, we obtain:

-2.15263...

rounded to 2 decimal places

-2.15