a set of six scores ranging from 1 to 12 is listed in numerical order. 1,2,a,7,b,12 the median is 5 and the mean is 6. what are the values of "a" and "b"?
Since the mean value is 6 the sum of all six scores must be 36 because
(mean=6 x numbers of scores=6)
an equation has appeared! : 1+2+a+7+b+12=36 -> a+b=14
We can't solve this one without another equation.
The median value is in this case the mean value of the two numbers in center (a and 7)
we know that the median is 5.
Therfore (a+7)/2=5 --> a+7=10 a=10-7=3
a=3 gives 3+b=14 in the firat equation.
b=14-3
answer: a=3. b=11
