Math Answers

John's commute from home to work is normally distributed with mean 45 minutes, deviation

standard 3 minutes.

a) What is the probability that John travels from home to work in 30 to 40 minutes?

b) If the starting time at the company is 9:00 am, what time should John start going from home?

so that the probability of getting to work on time is 95%?

In a group of 35 ex-athletes, 17 play golf, 20 go cycling, and 12 do yoga. Exactly 8

play golf and go cycling, 8 play golf and do yoga, 7 go cycling and do yoga, and 4 do

all three activities. How many of the ex-athletes do none of these activities?

Consider a small unit of a factory where there are 5 employees : a supervisor and four labourers. The workers earn a salary of Rs. 5,000 per month each while the supervisor gets Rs. 15,000 per month. Calculate the mean, median and mode of the salaries.

Given x ̅ = 60, s = 8.Find the z-score value of raw score 78 up to two decimal places

 Consider a population consisting of 4, 7, 8, 13, 15 and 17. Suppose samples of size 3 are drawn from this population. Determine the total number of samples.

Write the series 2 + 9 + 28 + 65 + ⋯ in Sigma notation. 

A company makes electronic gadgets. One out of every 50 gadgets is faulty, but the company doesn't know which ones are faulty until a buyer complains. Suppose the company makes a Php 200 profit on the sale of any working gadget, but suffers a loss of Php 4, 000.00 for every faulty gadget because they have to repair the unit.

Suppose the mean blood glucose of a population of adults is 162 with a standard deviation σ=58. From sample sizes of 36 adults find the proportion of sample means having values of at least 170.

Suppose it is known that the mean and the standard deviation for a given population are 65 and 8, respectively. What is the probability that a sample of 100 drawn from this population will have a mean greater than 66?

A sample of 169 is drawn from a certain population. This sample has a mean of 80 and a standard deviation of 10. Find the standard error of the mean.