Okay. I am attaching an image for number 25. Now for number 26, the possibilities with this question are endless...lol. Pi is an irrational number and the easiest, for me anyway, to give two real-life examples.
I needed my son to install a circular light fixture, so of course, we needed to figure the circumference of the. We use pi (3.14) with r as the radius.
The second example would be the speedometer of a car. Pi is used to determine the calibration needed.
I hope these help.
Take care,
Diana