homeschool girl
Junior Member
- Joined
- Feb 6, 2020
- Messages
- 123
Marvin the fly starts at [MATH](0,0).[/MATH] Each step, Marvin moves one unit right or one unit up. He is trying to get to the point [MATH](5,7)[/MATH]. However, at [MATH](4,3)[/MATH] there is a frog that will eat him if he goes through that point. In how many ways can Marvin reach [MATH](5,7)[/MATH]?
I've tried [MATH]\frac{12!}{5!\cdot7!}-\frac{7!}{3!\cdot4!}[/MATH], but that was wrong.
I've tried [MATH]\frac{12!}{5!\cdot7!}-\frac{7!}{3!\cdot4!}[/MATH], but that was wrong.