gmat prep prob...

[willbeatthegmat]

The arthematic mean & SD of a certain normal distribution r 13.5 & 1.5.What value is exactly 2 SD less than the mean?

a)10.5
b)11
c)11.5
d)12
e)12.5

OA: a

[raunekk]

aM= 13.5

Sd= 1.5

2 Sd= 2 * 1.5 = 3

Exactly 2Sd less than the mean = 13.5 - 3 = 10.5

i.e A

i hope it helps.

[willbeatthegmat]

tat looks preety simple..or mayb coincidentaly u hve arrived to d same ans..