Question

5000 students were appeared in an examination. The mean of marks was 39.5 with a standard deviation 12.5 marks. Assuming the distribution to be normal find the number of students recorded more than 60% marks Given: When Z = 1.64 Area of normal curve = 0.4495​

Answer 1

thanks s question answer is 252

Answer 2

8. 5% of the electric bulbs manufactures by a company are defective. Using normal approximation, find the probability

that in a sample of 400 bulbs, 30 or more will be defective. (2.29