Hi! You must be a 4th grader like me.
Luckily, I tutor all math units (no you can't meet me in real life you silly goose).
FOLLOW THESE INSTRUCTIONS :
- Draw 4 giant circles on a large sheet of paper.
- Draw 9 ten rods in each circle, adding 1.
- Count all of those by 10s. (adding the 1 of course.)
You've got your answer!
Really hope this helped. And if not, I apologize - really. It's my responsibility if you got an F.
Or you can just do 91x4.
XD Whichever you wanna do.