How woulld yo answer this question and get all three marks?

The width of a square is increased by 15%. Calculate the percentage change in the area of a square?

thank you

xx

Printable View

- May 17th 2008, 07:55 AMlivyg123percentage change
How woulld yo answer this question and get all three marks?

The width of a square is increased by 15%. Calculate the percentage change in the area of a square?

thank you

xx - May 17th 2008, 08:34 AMUnenlightened

Ok, you'd start off with a square, with four equal sides. Let's assign 100 to be the length of each of these sides. This means the area of the square is 100 * 100 = 10000.

The width of the square is increased by 15%, (turning it into a rectangle), So now you have two sides of 100 and two of 115.

110 * 115 = 11500 is the new area

The change is 11500-10000 = 1500.

As a percentage: 1500/10000 * 100 = 15%

I think...