Problem: How to calculate standard deviation
Look at your data set.
This is an important step in any type of statistical calculation, even if it is a simple figure like the mean or median.
Know how many numbers are in your sample.

Answer: Do the numbers vary across a large range? Or are the differences between the numbers small, such as just a few decimal places? Know what type of data you are looking at. What do your numbers in your sample represent? This could be something like test scores, heart rate readings, height, weight etc.

Problem: In the background people are practicing gymnastics and moving the mats. Women are doing somersaults together in a choreography. a woman

Answer: is doing somer saults and big jumps alone.

Problem: How to get a guy to dance with you
Wear something suited to the venue.
If you're going to a salsa or vintage jazz club, you might want to wear something that reflects the theme. You usually don't have to buy a whole new outfit or anything, but it can't hurt to make an effort to look nice.
Answer: Guys will notice and appreciate that you dressed up for the evening. Leave the stilettos and high heels at home.