What is between 3/8 in a number line

Okay I hope this is what you mean. so if you are saying what is between the numbers 3 and 8 we can make an inequality which will cover all the small decimals between the numbers.

There are 2 different equalities that I'm not sure which one you want.

so the first one would be

x is just the variable I chose for this. Now this inequality means that both 3 and 8 are solutions to the problem. x represent all the little numbers in between so to test your answers just plugin the number you're testing in for x. Since 3 is the lowest number it will have a less than or equal to (in this case) sign and 8 is the greatest so that's why the open/greater side is facing the 8. It reads 3 is less than or equal to x and x is less than or equal to 8.

If you meant all number in between 3 and 8 not include either of those numbers than the inequality would be

In this case all the numbers between 3 and 8 are solutions but 3 and 8 will not be solutions. the line under the symbol means it includes the number which come before or after it. The inequality reads 3 is less than x which is less than 8. You can also plugin in an answer to test it in place of x.

If you have any questions or it turns out you meant somthing else please tell me and I'll be happy to help, sorry if this isn't what you meant in the question.