Wrong scale

Hi everyone, I encountered an incorrect scale in the PDF file. :expressionless:
I have downloaded a map with scale 1:5000
Imported it in corel draw or illustrator and the dimensions are correct = 723,9x422,275mm (the same I can see in acrobat)
but If I measure two point: 736mm x 5000 (1/5000) = 3,68km
instead on google maps or oruxmap the distance is correct = 2.12km
Thanks.