What is a one-sentence summary of the following article?
If, during your practice run, you find that your time has elapsed before you could get through your whole presentation, you’ll know that your presentation has too many slides.  Head back to the drawing board to edit it accordingly.  If your presentation ended well before the time limit you’ve been given, try to extend the amount of time you spend on each slide, or add extra slides to expand on the info introduced in the presentation. Solicit advice from family and friends during your practice presentation.  If they feel there are too many or too few slides, or if they feel certain sections of the presentation felt rushed or slow, adjust your presentation to correct these deficiencies. If you speak quite quickly, you will be able to get through a great number of slides.  If, on the other hand, you speak more slowly, you’ll probably require a smaller number of slides.  Use your rate of speech to determine how many slides your presentation can accommodate. If you have ten minutes to present, you might need upwards of 60 slides.  On the other hand, you might also need just ten slides.  Whatever number you settle on, do not include more slides than you can get through in your allotted presentation time. If you have a lot of info which would be of use in your PowerPoint, or have graphs, tables, or images available that could improve your presentation, use them.  While you don’t want to include so many slides that you can’t get through them all in the allotted time, neither should you feel constrained to the point that you don’t include valuable information or graphics in your slideshow.

Summary:
Practice your presentation in front of a mirror or a small audience of friends and family before you do it for real. Think about the speed at which you speak. Do not use too many slides. Do not use too few slides.