Question

The mean age of a herd of cows is 7.9 years. A cow that is 0.5 years old is added to the herd. How does this cow’s age affect the mean?

A. The new mean age will be less than 7.9 years.
B. The new mean age will be 0.5 years.
C. The new mean age will still be 7.9 years.
D. The new mean age will be greater than 7.9 years.

Answer 1

Is the new cow's age less than the mean or greater than the mean?

Note: Choice "b." is silly. This is good only if the original cows all die.

Answer 2

C ?

Answer 3

No guessing.

3, 4, 5, 6, 7 ==> Mean = 5
Add a young one.
2, 3, 4, 5, 6, 7 ==> Mean = 4.5
Which way did it go?

Just to be thorough, if there are millions of cows, adding one of any age won't do much, but it will do something.

Answer 4

It will be less since its adding a young one

Answer 5

Are you asking or telling? What is the answer?

Answer 6

I'm asking

Answer 7

Your statement is correct. So out of the options, which one do you think it is knowing this information?

Answer 8

A?

Answer 9

You are correct! =)

Answer 10

@BlazeRyder

Answer 11

I'm here!

Answer 12

Again, it is a bad question.

If you have 1,000,000 cows at the start, that's 7,900,000 cow years.
Adding one 1/2 yearling gives. 7,900,000.5/1,000,001 = 7.8999926000 That's not a lot less than 7.9. If we are rounding to even 4 decimal places, it's still 7.9.

As long as we don't know anything about rounding, then we're good.