Answer:
86.64%
Step-by-step explanation:
We solve for the above question using z score formula
z score formula = z = (x - μ)/σ
where
x is the raw score
μ is the population mean
σ is the population standard deviation.
For x = 350, μ = 500, σ = 100
z score = 350 - 500/100
= -150/100
= -1.5
Using the z score for normal distribution
Probability (z = -1.5) = P(x = 350).
= 0.066807
For x = 650, μ = 500, σ = 100
z score = 650 - 500/100
= 150/100
= 1.5
Using the z score for normal distribution
Probability (z = 1.5) = P(x = 650).
= 0.93319
The probability of people who write this exam and obtain scores between 350 and 650
P < 350 < x < 650 = P(x ≤ 650) - P(x ≤ 350)
= P(z = 1.5) - P(z = -1.5)
= 0.93319 - 0.066807
= 0.866383
Therefore, the percent of people who write this exam and obtain scores between 350 and 650 is
0.866383 × 100
= 86.6383%
Approximately ≈ 86.64%
