the mean of 4 numbers is 31. What is the fourth number if 3 of the numbers are 37,15,22
4 * 31 = 124
37 + 15 + 22 = 74
124 - 74 = 50
Ms. Sue is correct.
To find the fourth number, we need to make use of the fact that the mean of the four numbers is 31. The mean (also known as the average) is calculated by summing all the numbers and dividing by the total count.
Here are the steps to find the fourth number:
Step 1: Add the given numbers.
37 + 15 + 22 = 74
Step 2: Calculate the total count of numbers.
We have three numbers already: 37, 15, and 22. So the total count is 3.
Step 3: Use the mean formula to find the sum of all four numbers:
Sum of four numbers = Mean × Total count
Sum of four numbers = 31 × 4 = 124
Step 4: Subtract the sum of the given three numbers from the sum of all four numbers to find the fourth number.
Fourth number = Sum of four numbers - Sum of given three numbers
Fourth number = 124 - 74 = 50
Therefore, the fourth number is 50.