dcsushant wrote:
For a certain set of 3 numbers, is the average (arithmetic mean) equal to the median?
(1) The range of the set is double the difference between the smallest number in the set and the middle number.
(2) The set consists of the three numbers 10, 16, and 22.
let three numbers be x,y,z. Also we know that for an evenly spaced numbers mean= median.
suppose x,y,z are evenly spaced i.e. differene between first and second, and second and third is same. thus we have
y-x=z-y
or 2y=x+z---------------------1)
let's consider st.1:
z-x=2(y-x)
z-x=2y-2x
2y=z+x
as can be seen from 1, thus these numbers are evenly spaced. hence mean=median. therefore statement 1 alone is sufficient.
st.2 again clearly sufficient. as value of x,y,z are given to us.
hence answer should be D