How to Reduce Images Using the Scale Factor for Geometry

The Scale Factor is a geometric term that can be defined as the ratio between two geometric objects with identical aspect ratios. The Scale Factor can also be used as a multiplier when it comes to scaling, which is useful for resizing images on your computer. If it needs to be reduced by a specific amount, like half or three-fourths, use the Scale Factor (“.5” or “.75” in this case) to make the reduction in size.

  1. Right-click on your image and select “Properties.” Open the “Details” tab to find out the current dimensions (in pixels) of your image. Note them down or commit them to memory.

  2. Go to the Windows Start menu, click “All Programs,” click “Accessories,” and then click “Calculator.”

  3. Type the width of the image into the calculator and then multiply it by the Scale Factor you want to reduce it by. For example, if you want to reduce it by half, multiply it by 0.5. If you want to reduce it by one quarter, multiply it by 0.25. Take note of the answer.

  4. Repeat the previous step for the height of the image using the same Scale Factor (e.g., 0.5 or 0.25). Take note of the answer.

  5. Open your image-editing program and select the “Resize image,” or similarly named, option from the menu bar. Type the answer from Step 3 in the “Width” text field and the answer from Step 4 in the “Height” text field. Click the “Apply” or “OK” button to reduce your image by the Scale Factor you used.

  6. Open the “File” menu and select “Save As” to save a new copy of your resized image.

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