Answer:
Process to proof Theorem and Formula nrealted to natural number.......
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.
Answer:
61
Step-by-step explanation:
- 13 - 1 = 12
- 12 ÷ 2 = 6
- Put 6 and 1 together: 61
Therefore, the number is 61
Let's check:
- 6 × 2 = 12
- 12 + 1 = 13
The sum of the two digits is 13, and we got that, so we are correct. The number is 61.