# BC Question PAT

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#### goutamk

##### Full Member
5+ Year Member

I was wondering how there are 18 cubes since I only counted 17? It also said that one of the cubes had 0 sides painted and the only possible one that I can think of is the one at the bottom of the stack of 3 but doesn't that mean that there must be a cube behind it? I thought that we weren't allowed to assume that cubes are present (if hidden from sight) unless they're needed for support.

#### nornton

##### Full Member
I see 18. Since there is an outline of a cube behind the stack of 3 then you assume there is a cube there. Does that make sense?

#### Elysian12

##### Full Member
5+ Year Member
Starting with the back row
tallest stack: 5 cubes
left of that: 2 cubes
and most left: 1
Middle row
far right: 1 cube
left of that: 3 cubes
most left: 2 cubes
And then the 4 single front ones

Total: 18

Your reasoning is correct so you should be getting 18 cubes