If x is a positive number less than 10, is z greater than the mean of x, and 10?
1. On the number line z is closer to 10 than to x
2. z = 5x
1. On the number line z is closer to 10 than to x
2. z = 5x
Statement (1)
Sufficient
if z is closer to 10, 10-z > z-x
Keeping that in mind let's plug in some values.
x=2, z=7
Mean of x and 10 = 6 < z
If x=0.5, z = 5.26 (It has to be closer to 10. So it has to be > 0.5+5.25)
Mean = 0.5+10/2 = 5.25 < z
Therefore z is always going to be more than the mean of x and 10
If z is closer to 10 than it is to x it must be greater than the mean of 10 and x . So (1) is sufficient
Statement (2)
z=5x
x=1, z=5
Mean = 1+10/2 = 5.5 > z
x=1.5, z=7.5
Mean = 1+10/2 = 5.5 < z
So statement 2 is insufficient.
Ans A
