Let's
a. 50%=2*40 y.old
b. 25%=60 y.old

For example, ((2*40)+60+x(we can take the lowest - 20))/4=160/4=40

So we need a & b to solve this problem, but I thing this is the problem from DS.

It must be C.Whats the OA?

Consider 100 people in the company.

A - 50% are aged above 40 years. i.e: 50 are above 40 years. Let's assume the rest 50 are 20 years old (Minimum possible from the question).

Total Age / Total number = 3000/100 = 30. So, Avg age Above 30 years. NOT SUFFICIENT.

B - 25% are aged above 65. Calculating similarly as above,
Total = 25*60 + 75*20 = 3000. Avg = 3000/100 = 30.

Together, 25% above 60 years, Another 25% above 40 years. Remaining 50% 20 years.

Total = 25*60 + 25*40 + 50*20
= 1500 + 1000 + 1000 = 3500.

Avg = 35. SUFFICIENT.

Thanks for help. I don't have the ans but I am confident its C. Do we get these small little question in GMAT?

CrackGMAC wrote:Thanks for help. I don't have the ans but I am confident its C. Do we get these small little question in GMAT?

To me, this is not a little question. I f you find this easy, cheer up, the test is full of them.

enniguy wrote:It must be C.Whats the OA?

Consider 100 people in the company.

A - 50% are aged above 40 years. i.e: 50 are above 40 years. Let's assume the rest 50 are 20 years old (Minimum possible from the question).

Total Age / Total number = 3000/100 = 30. So, Avg age Above 30 years. NOT SUFFICIENT.

B - 25% are aged above 65. Calculating similarly as above,
Total = 25*60 + 75*20 = 3000. Avg = 3000/100 = 30.

Together, 25% above 60 years, Another 25% above 40 years. Remaining 50% 20 years.

Total = 25*60 + 25*40 + 50*20
= 1500 + 1000 + 1000 = 3500.

Avg = 35. SUFFICIENT.

If hte question says "more than 20 years old", why you assume that employees are 20,40, or 60 ????

heshamelaziry wrote: If hte question says "more than 20 years old", why you assume that employees are 20,40, or 60 ????

I am assuming the least possible for every case.

enniguy wrote:

heshamelaziry wrote: If hte question says "more than 20 years old", why you assume that employees are 20,40, or 60 ????

I am assuming the least possible for every case.

Ok. I just thought of this:

If choice A reveals average age 30 and choice B reveals average age of 30, then each statement alone is Sufficient.

Please,advise.

CrackGMAC wrote:Thanks for help. I don't have the ans but I am confident its C. Do we get these small little question in GMAT?

If choice A reveals average age 30 and choice B reveals average age of 30, then each statement alone is Sufficient. We only need to answer the question By either YES or No.

According to the solution. OA should be D. Each statement alone is sufficient, because each gives the answer to be NO.

I think it should be C.

Sample size = 100.

1) 50% > 40 yrs old -
Age = 41, and 21 (b/c, >40 and >20)
[50(41)+50(21)]/100 = 31. 31 < 35 which means that the avg age could be above OR below 35. INSUFFICIENT

2) 25% > 60 yrs old -
Age = 61 and 21
[25(61)+75(21)]/100 = 31. 31 < 35. same situation as above. INSUFFICIENT

1) & 2) - [50(41) + 25(61) + 25(21)]/100 = 41. SUFFICIENT, b/c we used the minimum age for each given piece of info.

therefore, C.

Maybe I'm wrong. I don't understand why you say D. Please explain.

C it is!!!

Use weighted averages:

1) .5*40 + .5*20 = 24 insufficient
2) .25*60 + .75*20 = 30 insufficient

combined .5*40+.25*60+.25*20=40 sufficient