Cross Multiplication Refresher

cross multiplication

I don’t use algebra everyday so when a problem happens to come up I have to stop and think for a minute.  I thought maybe this refresher and my example might be useful to others so I am sharing my actual math problem.

As I have mentioned before, I use PowerPoint to create images for this blog and I wanted to start creating them at the size they will appear when posted.  This way they will be the right size in RSS feed, I won’t have a second step of resizing, and hopefully it will speed up my site (because I have been posting them bigger than they need to be).  I had just created this image and the PowerPoint slide dimensions were 5 inches wide by 15 inches tall.  When I saved the slide as a PNG it automatically sized it at 480 dpi wide.  I want the large images on my blog to be 600 dpi wide.  I know that if I size my slide 5 inches wide I will get 480 dpi wide output.  So, if I want 600 dpi wide output I need to size my PowerPoint slides to be 6.25 inches wide.  I reached this conclusion with cross multiplication.  See step by step above!

Math is like magic sometimes!  How do you feel about math?  Please share!



I'm a practical mom inspired by nature & I enjoy sharing ideas that encourage kids' innate curiosity & creativity. Interested in subscribing? Check out the blue box at the top of my sidebar. I'm also a wannabe author/illustrator & product designer by day. Let's connect! If you purchase through my Amazon links I get a small commission at no additional cost to you (thanks for supporting Doodles and Jots)! And remember to always credit your source here & elsewhere on the internet.


  1. Math gets me out of all kinds of trouble. I need basic math skills every single day – to solve all kinds of problems. Math is essential. We need not ruin our kids into thinking they are bad at math. Everyone learns at their own pace.

    Math is fun!

    Thanks so much for sharing your problem.
    Lisa Nelson recently posted..5 Among Friends – QuestionsMy Profile

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

CommentLuv badge