Determine the missing values [tex]\(A\)[/tex], [tex]\(B\)[/tex], and [tex]\(C\)[/tex].

Use the following formula:
[tex]\[ \text{Total cost} = \text{Fixed monthly cost} + (\text{number of curtains} \times \text{cost per curtain}) \][/tex]

Table 1: Production costs for different quantities of curtains.

[tex]\[
\begin{tabular}{|c|c|c|c|c|c|c|c|c|}
\hline
\begin{tabular}{c}
Number \\
of \\
curtains \\
produced \\
($n$)
\end{tabular} & 0 & 30 & 40 & 51 & 56 & 60 & 70 & $C$ \\
\hline
\begin{tabular}{c}
Total \\
cost (R) \\
per \\
month
\end{tabular} & 1000 & 4000 & $A$ & 5335 & 5760 & $B$ & 6950 & 7290 \\
\hline
\end{tabular}
\][/tex]



Answer :

To determine the missing values [tex]\( A \)[/tex], [tex]\( B \)[/tex], and [tex]\( C \)[/tex] in the table, we can use the given data and formula. Here’s a step-by-step solution:

1. Given Data:
- Fixed monthly cost when no curtains are produced = \[tex]$1000. - Costs for different numbers of curtains produced: - 30 curtains: \$[/tex]4000
- 51 curtains: \[tex]$5335 - 56 curtains: \$[/tex]5760
- 70 curtains: \[tex]$6950 - C curtains: \$[/tex]7290

2. Step 1: Calculate Cost Per Curtain:

We need to find the average cost per curtain by using the given costs for different quantities.

- For 30 curtains:
[tex]\[ \text{Cost per curtain} = \frac{4000 - 1000}{30} \][/tex]

- For 51 curtains:
[tex]\[ \text{Cost per curtain} = \frac{5335 - 1000}{51} \][/tex]

- For 56 curtains:
[tex]\[ \text{Cost per curtain} = \frac{5760 - 1000}{56} \][/tex]

- For 70 curtains:
[tex]\[ \text{Cost per curtain} = \frac{6950 - 1000}{70} \][/tex]

Next, find the average cost per curtain:
[tex]\[ \text{Average cost per curtain} = \frac{\left(\frac{4000 - 1000}{30} + \frac{5335 - 1000}{51} + \frac{5760 - 1000}{56} + \frac{6950 - 1000}{70}\right)}{4} \][/tex]

3. Step 2: Calculate Missing Values [tex]\(A\)[/tex], [tex]\(B\)[/tex], and [tex]\(C\)[/tex]:

- For [tex]\(A\)[/tex] (Cost for 40 curtains):
[tex]\[ A = 1000 + (\text{Average cost per curtain} \times 40) \][/tex]

- For [tex]\(B\)[/tex] (Cost for 60 curtains):
[tex]\[ B = 1000 + (\text{Average cost per curtain} \times 60) \][/tex]

- For [tex]\(C\)[/tex] (Number of curtains produced when cost is \$7290):
[tex]\[ C = \frac{7290 - 1000}{\text{Average cost per curtain}} \][/tex]

4. Final Values:

After doing the above calculations (which have been provided), we get the following values:

[tex]\[ A = 4550.0 \][/tex]
[tex]\[ B = 6325.0 \][/tex]
[tex]\[ C = 70.87 \approx 71 \; \text{(nearest whole number of curtains)} \][/tex]

So, the missing values in the table are:
- [tex]\( A = 4550.0 \)[/tex]
- [tex]\( B = 6325.0 \)[/tex]
- [tex]\( C = 70.87 \approx 71 \)[/tex]