How many blocks?

Question

Tara has 13 blocks. She uses some of the blocks to build a tower. The number of blocks she uses is the same as the number of blocks left over. How many blocks could Tara use to build her tower?

Answer 1

6 and 1/2

Yes, splitting 13 blocks evenly is entirely unrealistic...
And the problem is worded very poorly.
But it does say, how many blocks COULD she use...

Well she COULD use 3 which would leave 10 unused...
she COULD use 4 which would leave 9 unused....
she COULD use 5 which would leave 8 unused...
she COULD use 6 which would leave 7 unused...
she COULD use 7 which would leave 6 unused..,,
she COULD use 8 which would leave 5 unused....
etc etc etc..
None of those options are correct because the number
of blocks unused is different than the number of blocks used.
So now we are back to where we were.....

Half of 13 is 6 and 1/2