Re: Help needed with test

Quote:

Originally Posted by

**Kendall** Hi, I am new here and need your help!! I am trying to solve:

there are 15 yellow and 35 orange balls in a basket How many more yellow balls must be added to make the yellow balls 65 %

I got to this point

x + 15\x +50=65\100 and I can't move from here... Can someone guide me, please?

By the way, the answer is 50

I thought otherwise about this problem:

if 15 + x = 65% and 100% = (15 + x) + 35, thus

x = 100% - 50 = 50, we need to add 50,

dokrbb

Re: Help needed with test

Thank you, Dokrbb!! It makes total sense! I don't know what I was thinking when did it another way!

Thank you :)

Re: Help needed with test

Hello, Kendall!

Quote:

There are 15 yellow and 35 orange balls in a basket.

How many more yellow balls must be added to make the yellow balls 65% ?

Your set-up is absolutely correct!

Note that: $\displaystyle 65\% \,=\,\tfrac{65}{100} \,=\,\tfrac{13}{20}$

Let $\displaystyle x$ = additional yellow balls.

Then the basket contains $\displaystyle 50+x$ balls of which $\displaystyle 15+x$ are yellow.

We want: .$\displaystyle \frac{x+15}{x+50} \:=\:\frac{13}{20}$ . . . . You got this far.

Cross-multiply: .$\displaystyle 20(x+15) \:=\:13(x+50) $

n . . . . . . . . . . . $\displaystyle 20x + 300 \:=\:13x + 650$

n . . . . . . . . . . . . . . . . . $\displaystyle 7x \:=\:350$

. . . . . . . . . . . . . . . . . . . $\displaystyle x \:=\:50$

Re: Help needed with test

Since distribution does not change number of orange balls: ? + 35 = 100; ? = 65 ; 65 - 15 = 50

Re: Help needed with test

I realize I'm getting to this a bit late, but we aren't allowed to help with graded questions. Please do not do this again in the future! (That goes for helping the student as well, people!)

-Dan

Re: Help needed with test

Quote:

Originally Posted by

**topsquark** I realize I'm getting to this a bit late, but we aren't allowed to help with graded questions. Please do not do this again in the future! (That goes for helping the student as well, people!)

-Dan

Hi Totsquark,

Sorry I should be more clear when posted, it is **not graded test**, it is for practice, otherwise I wouldn't be able to ask a question, as I wouldn't have it :) We don't have assignments that we could take home...

Re: Help needed with test

Thank you everyone for all your help!! This board is the best!

Re: Help needed with test

Quote:

Originally Posted by

**topsquark** I realize I'm getting to this a bit late, but we aren't allowed to help with graded questions. Please do not do this again in the future! (That goes for helping the student as well, people!)

-Dan

What's the problem Dan?

He ALREADY had 50 as the answer: shown in his initial post.

Re: Help needed with test

Quote:

Originally Posted by

**Wilmer** What's the problem Dan?

He ALREADY had 50 as the answer: shown in his initial post.

He had the final answer, not the complete solution. There's a world of difference between the two.

-Dan

Re: Help needed with test

Quote:

Originally Posted by

**topsquark** He had the final answer, not the complete solution. There's a world of difference between the two.

-Dan

OK Dan, you are making it all so difficult, sorry for even posting here, I already regret that. I explained already that it is not FOR GRADING TEST. Who would actually give us test in advance??? It just doesn't make sense... I had half of the solution and the answer, just wasn't sure about last step, please read it again.

I was very happy to find this forum and grateful for all the help, but if I am not allowed to ask questions about old test here it is fine, I will not come back here again:(

Re: Help needed with test

Quote:

Originally Posted by

**topsquark** He had the final answer, not the complete solution. There's a world of difference between the two.

Agree. But (from what I understand from other similar sites) we do not give the

answer (50 in this case) but will "help/teach" by giving the solution steps, perhaps

using a similar problem to demonstrate.

Anyhow, ain't looking for an argument (I'm not a moderator, just an average helper).

I showed the actual "50" in my reply only because it had been already shown

by Soroban.

Re: Help needed with test

Quote:

Originally Posted by

**Kendall** OK Dan, you are making it all so difficult, sorry for even posting here, I already regret that. I explained already that it is not FOR GRADING TEST. Who would actually give us test in advance??? It just doesn't make sense... I had half of the solution and the answer, just wasn't sure about last step, please read it again.

I was very happy to find this forum and grateful for all the help, but if I am not allowed to ask questions about old test here it is fine, I will not come back here again:(

I'm sorry you are taking issue about this, but the fact of the matter is that there have been several people in the past who have gotten take home tests and tried to get us to solve their exam for them. In the future if it's a practice exam or some such simply tell us it's not for credit.

-Dan