I came across a problem that seems impossible to solve. I'm posting this as part of a class project from CCA. The problem is that I don't know how to compute an answer when you need to know the answer before you can compute the answer.
The question:
What is the weight of a chicken, if the chicken weights 10 lbs + 1/3 of its weight?

This appears to be a very simple problem to me, but I have been chastised before for my answers. I will post my solution, and let the judges bring it on!

Let w = the chicken's full weight. Then, we can set up the following equation to find w:

10 + 1/3 w = w.

Clear the denominator of 3 by multiplying both sides by 3 as follows:

(3)(10) + (3)(1/3)w = 3w, getting
30 + w = 3w.

Subtracting w from both sides, we get 30 = 2w.

Dividing both sides by 2, we get 15 = w. Hence the full weight of the chicken is 15 lbs.

Notice that 1/3 w is 5 lbs. Add the 10 + 5 to get the 15.

We almost proved the solution, which we can do now:
10 + 1/3 w = w
10 + (1/3)(15) = 15
10 + 5 = 15
15 = 15.

tsaeb hopes that she redeemed herself with this solution. Now, tsaeb (half-cocked) leaves the next solution to you regulars. Don't forget: birds of a feather flock together, but this is not always true for humans.

[This message was edited by tsaeb on 10-23-02 at 01:35 AM.]

10 + (X*0.3) = X

or...

X-10 = X/3

Your answer:

(X-10)*3 =X

or(10*3)-X = X

or X + X = 10 * 3

Mr(no help at all)Sensitive

When you have a sum or difference that must be multiplied, you cannot remove an addend of subtrahend or minuend. There is a second way, similar to the first response, to solve this.

10 + w/3 = w
10 = w - w/3
10 = 2w/3
30 = 2w
w = 15