The mean of 10 number is 25. if 5 is subtracted from each other find the new mean.

The mean of 20 numbers is 43, if 6 is subtracted from each of the numbers, what will be the new mean?

The mean of 20 numbers is 18, if 3 is added to each of the first ten numbers, find the mean of the new set of 20 numbers.

There are 50 numbers. Each number is subtracted from 53 and the mean of the numbers so obtained is found to be -3.5. The mean of the given number is:

The mean of first 10 natural numbers is

If the mean of 8 observations be 15 and 2 be added to each observation, then the mean of new set of observations will be .

Form the pair of linear equations in the following problems and find their solutions (if they exist) by any algebraic method :-The sum of a two-digit number and the number formed by interchanging the digits is 110. If 10 is subtracted from the first number, the new number is 4 more than 5 times the sum of the digits in the first number. Find the number

Form the pair of linear equations in the following problems and find their solution by substitution method : If 1 is added to each of the two numbers, their ratio becomes 1 : 2 and when 5 is subtracted from each of these, the ratio becomes 5:11. Find the numbers.

The mean of 5 numbers is 18, if one number is excluded, their mean is 16. find the excluded number.

The mean of six numbers is 23. if one of the number is excluded, the mean of the remaining numbers is 20. find the excluded number.

The mean of 12 numbers is 40. if each numbers if divided by 8, what will be the mean of the new numbers?