Problem: Find the value of x, if the mean of 17, 12, 19, 20, x, 21and 22 is 18?

Solution:
To find the value of x, we need to use the formula for the mean or average:
Mean = Sum of all numbers / Total number of numbers

We know the mean of the given numbers is 18, so we can write:

(17 + 12 + 19 + 20 + x + 21 + 22) / 7 = 18

Now, we need to solve for x:

1. Simplify the left-hand side of the equation by adding all the numbers in the numerator:

111 + x = 126

2. Subtract 111 from both sides of the equation to isolate x:

x = 15

Therefore, the value of x is 15, if the mean of 17, 12, 19, 20, x, 21 and 22 is 18.

Explanation:
To find the value of x, we need to use the formula for the mean or average, which is the sum of all the numbers divided by the total number of numbers. In this case, we are given 7 numbers and their mean, so we can set up an equation with the mean on one side and the sum of the numbers on the other side. Then, we can simplify this equation to solve for x. In this case, we added all the numbers in the numerator and set it equal to the total sum multiplied by the mean. Finally, we solved for x by isolating it on one side of the equation.

It's simple ...18=17+12+19+20+X+21+23÷7 now....18×7=111+X then....X= 126-111 X=15 so if you like my answer please upvote me and follow me...