Question

I need help trying to understand how they solved this equation. Just a little confused.

Answer 1

0.495

Explanation:

Given the expression:

`0.55-1.645\sqrt[]{(0.55(1-0.55))/(220)}`

Begin by simplifying the expression under the radical (square root) sign.

`\begin{gathered} =0.55-1.645\sqrt[]{(0.55(0.45))/(220)} \\ =0.55-1.645\sqrt[]{(0.2475)/(220)} \end{gathered}`

Using a calculator, we evaluate the radical:

`\begin{gathered} =0.55-1.645\sqrt[]{0.001125} \\ =0.494825 \\ \approx0.495\text{ (to 3 decimal places)} \end{gathered}`