cmal wrote:1.Given A = {6, 6, 9,10,14,15}
B = {7, 9,10,11,14, 15}
Col A: Standard deviation of A
Col B: Standard deviation in B

2.Col A: Standard deviation of 50, 60, 70, 80 & 90
Col B: Standard deviation of 50, 55, 70, 85 & 90.
Answer B
Is the highest range equal to the highest Standard Deviation? Is that a short cut to this type of question?


3.Given that, if a person has 5 pair of socks of different colors and if 2 are chosen at random then what is the probability that both of them are of same color?

Ans= 1/9
Shouldn't the answer be = 1/10*1/9?


4.If standard deviation of 'p' number of people is 21.5 and standard deviation of 'q' number of people is 9 then what is that least possible standard deviation value when both p and q are added?
Don't know the answer some say 9 but I would say no possible

5.If two numbers when divided by 38 leave equal remainders. When divided by 19 the remainders are r and s.
Col A: r
Col B: s
Ans: C r=s
However I feel if we assume numbers let's say 3 and 4
So 38/3 leaves a remainder of 2
And 38/4 leaves a remainder of 2
So 19/3 leaves a remainder of 1
And 19/4 leaves a remainder of 3
So the answer would be not possible? But it says C like both are equal r-s


6.You scored a 24 on your ACT math test. The mean for this exam is 21, with a standard deviation of 3. On the math SAT test, the mean is 500 with a standard deviation of 50. If you had taken the SAT what would your score have been?

450
503
550
553
650
none of the above
Ans= 550

7.Roger scored a 475 on the Math SAT test. What would he have scored if he had taken the ACT?

17
17.5
18.5
19.5
21.5
none of the above
Don't know answer?



8.A Student obtained the mean and standard deviation of 100 observations as 40 and 5.1 resp. later it was discovered that he had wrongly copied down an observation as 50 instead of 40. calculate true mean and standard deviation.?
Mean =39.9
Don't know how to calculate the standard Deviation



9.If std dev of x is 8,then variance of 5x+7 is?
Ans=1600 (How to Calculate Though)