Given:
The given sets are:
Set a : 200, 104, 100, 160.
Set b: 270, 400, 483, 300, x.
Mean of set a: mean of set b= 3:8
To find:
The value of x.
Solution:
Formula for mean:
The mean of set of a is:
The mean of set of b is:
It is given that,
Mean of set a: mean of set b= 3:8
Isolate the variable x.
Divide both sides by 3.
Therefore, the value of x is 427.
Micah was asked to add the following expressions:
First, he combined like terms in the numerator and kept the common denominator
First step is correct. He added the like terms in the numerator, because the denominators are same.
So he got ,
In the next step, he cannot cancel out x^2 from the top and bottom . Because x-4 and 3x+2 are added with x^2
If we have x^2 is multiplied with other terms at the top and bottom , then we can cancel out x^2.
So Micah added the expression incorrectly. Final answer is not correct.