SOLUTION: The height and base of a right angled triangle are 15cm and 20cm. If the height is increased by 60%, and the base reduced by 60%, what is the percent change in area?

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Question 1098526: The height and base of a right angled triangle are 15cm and 20cm. If the height is increased by 60%, and the base reduced by 60%, what is the percent change in area?
Found 4 solutions by josgarithmetic, MathTherapy, greenestamps, ikleyn:
Answer by josgarithmetic(39618)   (Show Source):
You can put this solution on YOUR website!

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Answer by MathTherapy(10552)   (Show Source):
You can put this solution on YOUR website!
The height and base of a right angled triangle are 15cm and 20cm. If the height is increased by 60%, and the base reduced by 60%, what is the percent change in area?

Correct answer:
IGNORE the nonsense posted by the other person!
STAMPSGREEN, or whatever!
You don't get it because you love to stick your nose into other people's business. You come here thinking that you know everything, and keeps criticizing
people because they don't use your LOGICAL methods.
No-one is interested in your LOGICAL methods. This is the 21st century. We have calculators, in case you don't know, and people are looking to solve math
problems as easily and quickly as they can. They're not going to sit in an exam and spend 1 hour using your LOGICAL way of thinking. They're NOT INTERESTED in
your LOGICAL WAY of solving, so stop criticizing people for using methods that people are familiar with and prefer to use. You even make fun of people
whose 1st language is Not English. Who do you think you are? Just butt out and keep out of other people's business. You know nothing so say nothing!
I'm tired of you old people coming in here and trying to dictate how people should do things.

Answer by greenestamps(13200)   (Show Source):
You can put this solution on YOUR website!

Dear tutor MathTherapy:

I don't get it. Another tutor posts a perfectly good, although not very efficient, solution to the problem. Then you provide an answer without showing any work at all, and you tell the reader to "ignore the nonsense" that the other tutor provided.

So you think that an answer with no indication whatsoever of how to solve the problem is more useful to a student than a solution that maybe uses a method you personally don't like??!!

To the reader....

You don't need to do anything with the given measurements of the triangle. All you need to know is that the formula for the area of the triangle is one-half base times height.

Since the formula is that straightforward, all you need to use to get the answer is to know that the height was increased by 60% and the base was reduced by 60%.

An increase of 60% means the height was multiplied by ; a decrease of 60% means the base was multiplied by . Then the area was multiplied by .

So the new area is 64% of what is was; that means the area was reduced by (100-64) = 36%.

Note a quicker way to see the answer of a 36% reduction is to look at the multiplying factors this way:

When you do the calculation this way, you immediately see that the answer is a reduction of 36%.

Answer by ikleyn(52788)   (Show Source):
You can put this solution on YOUR website!
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Dear tutor @greenestamps !

The tutor @josgarithmetic posted totally wrong solution,

and the tutor @MathTherapy quite correctly noticed it.

In response, the tutor @josgarithmetic fixed his post.

To be honest, we have hard time fixing his everyday errors.

If you joint us in this work fixing his numerous bugs, we will be happy !

If you replace me in this function, I will be happy !