Final answer:
To find the number of citizens older than 70 years old in the given barangay, we can calculate the z-score and use a standard normal distribution table or calculator to find the probability.
Step-by-step explanation:
To find the number of citizens who are more than 70 years old, we need to calculate the z-score for a value of 70, using the formula: z = (x - μ) / σ.
Substituting the values into the formula, we have: z = (70 - 43) / 12 = 2.25.
We can then use a standard normal distribution table or calculator to find the probability corresponding to a z-score of 2.25, which is approximately 0.9878. Multiplying this probability by the total population of 5000, we get: 5000 * 0.9878 ≈ 4939.