I.11 Arrangement of ● and ○

In accordance with a certain rule, ○ and ● are written as follows.

It stopped writing with the place which wrote eight ● exactly.

How many are there written in all ?

Answer

44 pieces

Solution

There are eight groups separated by dividing the line at ●. 

In every group there is one ●. 

In first group ○ is one there and in second group ○ is two. 

As you can find in eight group ○ is eight, ○ is 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 = 36. 

In total there are 8 + 36 = 44 pieces.