- 1 Marks
Question
The daily sales figures of a supermarket follow a normal distribution with a mean of N60,000 and a standard deviation of N14,000. Find the probability that the sales figure of a certain day exceeds N46,000.
A. 0.1587
B. 0.1590
C. 0.8413
D. 0.8415
E. 0.8423
Answer
Answer: C
Explanation: The correct answer is C. To solve, first calculate
Where:
- X=
- μ = 60,000 (mean)
- σ = 14,000 (standard deviation)
z = 46,000 − 60,000 / 14,000 = 1.0
From the z-table, the probability corresponding to z = -1.0 is 0.1587, which represents the probability that the sales figure is less than N46,000. The probability that the sales figure exceeds N46,000 is:
1−0.1587=0.84131 – 0.1587 = 0.8413
Thus, the probability that the sales figure exceeds N46,000 is 0.8413.
- Tags: Normal distribution, Probability, Sales Data
- Level: Level 1
- Topic: Probability
- Series: NOV 2014
- Uploader: Dotse