Average weight for a group of 20 women is 130 pounds....

[doubleu]

Q: The average weight for a group of 20 women is 130 pounds. If the average weight for 3/4 of these women was 140 pounds, what was the average weight, in pounds, for the rest of the women?

I know that the rest of the women would mean I have to figure out the average of the other 5 women. I'm not sure how to calculate the answer though.
Please help me.

 

[royhaas]

Calculate total weight first.

 

[TchrWill]

Re: Average Weight

The average weight for a group of 20 women is 130 pounds. If the average weight for 3/4 of these women was 140 pounds, what was the average weight, in pounds, for the rest of the women?

I know that the rest of the women would mean I have to figure out the average of the other 5 women. I'm not sure how to calculate the answer though.
Please help me.

The total weight of the 20 women is W(20) = 20(30)

The total weight of 3/4 of the women is W(15) = (15)(140)

The average weight of the remaining 5 women is -->I'll let you take it from here.

 

[doubleu]

Re: Average Weight

The average weight for a group of 20 women is 130 pounds. If the average weight for 3/4 of these women was 140 pounds, what was the average weight, in pounds, for the rest of the women?

The total weight of the 20 women is W(20) = 20(30)

The total weight of 3/4 of the women is W(15) = (15)(140)

The average weight of the remaining 5 women is -->I'll let you take it from here.

I got confused with the 20(130) typo but was able to figure it out. Thanks!

 

[Deleted member 4993]

For this problem - you don't need to know the "total number" of women in the group.

Let the average weight of the (1/4) of the women = A

From the definition of "simple" average (as opposed to "weighted average - just couldn't resist it),

3/4 * 140 + 1/4 * A = 130

420 + A = 520

A = 100

 

[TchrWill]

Re: Average Weight

The average weight for a group of 20 women is 130 pounds. If the average weight for 3/4 of these women was 140 pounds, what was the average weight, in pounds, for the rest of the women?

The total weight of the 20 women is W(20) = 20(30)

The total weight of 3/4 of the women is W(15) = (15)(140)

The average weight of the remaining 5 women is -->I'll let you take it from here.

I got confused with the 20(130) typo but was able to figure it out. Thanks.

I don't know what you meant by the 20(130) typo.

20(130) = 2600
15(140) = =2100

Therefore, Wa(5) = 500/5 = 100.

 

[stapel]

I don't know what you meant by the 20(130) typo.

TchrWill: I could be wrong, but I think the poster was referring to the highlighed portion of your work, where you gave the total weight of the twenty women as being the product of 20 and 30, rather than of 20 and 130. No biggie: Typoes happen to the best of us! :wink:

Note to "doubleu": I'm glad you stuck with it, not giving up as soon as you were confused. You followed the reasoning, continued to work, and figured it out in the end. Good job!

Eliz.

 

[TchrWill]

TchrWill: I could be wrong, but I think the poster was referring to the highlighed portion of your work, where you gave the total weight of the twenty women as being the product of 20 and 30, rather than of 20 and 130. No biggie: Typoes happen to the best of us! :wink:

Thanks for turning the lights on. I found the typo.

Thanks

Bill

 

[doubleu]

Yes stapel, that was the typo I was referring too.

Subhotosh Khan it's nice to know of other ways to solve it.

Thanks for the help everyone.