Use the basic formula to find the mean of this data.

Total numbers are 50. So, we are actually subtracting 53_50 from the sum of 50 terms. We can get the new sum as negative number by using the formula of mean.

Think about the formula of mean which can be used in this question.

Think about the sum of ages of all members and then find total age of majors.

Find the total sum of original observations by using the formula of mean. Then, add the difference of 70 and 170 to the orignal sum. Then, find the final mean.

Think about the methods which we can use to measure the central tendency.

Calculate the total sum of five terms and put it in the formula of mean to calculate the velue of x.

Find the total sum of all 15 observations. Then, find the total of first 8 and last 8 observations.

The whole numbers start from where?

Use the formula of mean and find the total sum of five numbers and then sum of the remaining four numbers.