Lovers Meet - Part 3
Probability
Level
2
Anna and Ben live at opposite corners of a 2 by 4 block.
If Anna only moves right or up or down, and isn't allowed to retrace her steps, how many ways does she have to get to Ben?
12
8
6
10
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Initially, she can go right or down->right.
If she goes right:
She can now go right or down->right
If she goes right she can go down->right or right->down.
If she goes down->right, she can go up->right->down or right.
If she goes down->right:
She can now go up->right or right
If she goes up->right, she can go down->right or right->down.
If she goes right, she can go up->right->down or right.
Counting the cases gives total cases 8