X=2 because 3 minus 1 equals 2
Answer:
The minimum sample needed to provide a margin of error of 3 or less is 52.
Step-by-step explanation:
The confidence interval for population mean (<em>μ</em>) is:

The margin of error is:

<u>Given:</u>
MOE = 3
<em>σ </em>= 11
The critical value for 95% confidence interval is: 
**Use the <em>z</em>-table for critical values.
Compute the sample size (<em>n</em>) as follows:

Thus, the minimum sample needed to provide a margin of error of 3 or less is 52.
Do you need an equation?
y=2x+10
2x represents each hour, 10 represents renting fee
There are two ways you can write it:
1. 30 + 6 + (1 × 1/10) + (3 × 1/100)
2. 30 + 6 + 0.1 + 0.03
Either is correct :)