Here was my question
The mean height of 5 students is 59.4. If one of the students leaves, the mean height becomes 61. What is the height of the absent student?
Heres Bob's answer but what does set them equal mean?? SOMEONE HELP!
math - bobpursley, Wednesday, May 26, 2010 at 11:07pm
total height: 5*59.4
total height: 4*61+absentstudent
set them equal, and solve for absent student height.
4*61 + absentstudent = 5*59.4
is that the answer though? I am still not following because then that would mean the kids height was 542 ???so confused
ok , let x = absentstudent
4*61 + x = 5*59.4
244 + x = 297
x = 297-244
x = 53
When Bob mentions "set them equal", he is referring to the equation that is created by equating the two expressions for the total height.
To solve the problem, we need to set up an equation using the given information.
Let's assume the height of the absent student is represented by "x".
The total height of the 5 students is the mean height of 5 students (59.4) multiplied by the number of students (5). So, the expression for the total height of the 5 students is: 5 * 59.4.
When the absent student leaves and only 4 students remain, the mean height becomes 61. So, the new expression for the total height of the 4 students becomes: 4 * 61.
Since the total height remains the same regardless of whether the student is present or absent, we can set up an equation by equating the two expressions for the total height:
5 * 59.4 = 4 * 61 + x
By simplifying this equation, we can solve for the height of the absent student (x).