Question

insert 100 rational numbers between -3/13 and9/13

Answer 1

There is one easy way,
convert them into decimals, -0.2307 and 0.6923.
Now you can easily insert 100 numbers like 0.6922,0.6921.0.6920.... and so on or any other number you wish.
If you want numbers in fraction then convert them back from decimal to fraction. like 6922/1000, 6921/1000..... and so on.

hope it helps :)