It takes 3 brick layers 2 hours to build a wall how long would it take 4 brick layers please show steps in ratio

Ratios are basically proportions so in this scenario

We can make it…

brick layers : hours

We’re given the first one which is

3:2

Whilst the one we need to find is only given for brick

For the unknown hours we can make it “x”

4: x

Now we have 2 ratios

3:2

4:x

Now these are fractions and we can make them equal to each other by

3/2 = 4/x

Now cross multiply to solve for x

3x=8

2 2/3 = x

So 2 2/3 hours

(A) With 99% confidence, the proportion that favours the Green initiative is between 418.895 and 423.105 (no approximation; answers were gotten exactly in 3 decimal places).

(B) If many groups of 593 (greater than the initial sample size of 556) randomly selected Americans were surveyed then a different confidence interval would be used or produced from each group.

About 90% of these confidence intervals will contain the true population proportion of Americans who favour the Green initiative and about 10% will not contain the true population proportion.

Step-by-step explanation:

(A) 99% of 421 = 416.79

421 - 416.79 = 4.21

4.21 ÷ 2 = 2.105

(421-2.105), (421+2.105)

The lower and upper limits are:

[418.895 , 423.105]

(B) A wider confidence interval such as 90% will be better suited in a case of multiple samples like this.