Story Problem Help Needed

[warnermonarch]

The height of Deception Island is 2119 feet shorter than the height of Kilauea. The height of Kilauea is 229 feet more than two times the height of Deception Island. What is the height of Kilauea.
I have tried k-2119 = 2(k-2219) + 229 - I get 1890 and that is not correct - 4009 is the correct answer, but I need to understand why!

 

[mmm4444bot]

I have tried

k - 2119 = 2(k - 2219) + 229 -

Is the trailing minus sign a typographical error?


I get 1890

I don't see how, from the (incorrect) equation above; why do you not show your work?


4009 is the correct answer Yes, I think that it is.

Please check out the post titled, "Read Before Posting". It provides information on how to properly request help on these boards.

Let's review some basics.

With almost all word problems, after you understand the given information, the next step is to write down definitions for all symbols that you choose. You did not define symbol k, but I think that you mean the following.

k = the height of Kilauea (in feet)

Since we're told that Deception Island is 2119 feet shorter than Kilauea, we can immediately write the following definition.

k - 2119 = the height of Deception Island (in feet)

You set up the following equation (I'm ignoring the trailing minus sign):

k - 2119 = 2(k - 2219) + 229

You somehow solved this equation, arriving at k = 1890. That is not a correct solution to this equation.

The correct solution to this equation is k = 2090

[If you try to find why, and cannot figure out your arithmetic mistake(s), please post your work.]

Yet, "Kilauea is 2090 feet high" is not the answer to this exercise, either. Your setup is not correct.

Your equation represents the following statement.

"The height of Deception Island is the same as twice its height plus an additional 229 feet."

That's not what the given information states.

Perhaps, a different approach will seem clearer, to you. Let's introduce another symbol.

d = the height of Deception Island (in feet)

Now, we can do the following.

From the given information, "Deception Island is 2119 feet shorter than the height of Kilauea", we get:

k - d = 2119

This means:

k = d + 2119

We're told that k is the same as 2d + 229, so we can setup the following equation.

d + 2119 = 2d + 229

Solve this equation, to find the height of Deception Island. Add another 2119 feet, to get 4090 feet for Kilauea.

If you would like more help with this exercise, please post your work, ask a specific question, or explain why you're still stuck.

Cheers ~ Mark

 

[warnermonarch]

Thank you! You have made the problem much easier to understand. I can see where my original equation was incorrect.