In Draw, rectangle box of 1.50 cm wide by 2.50 cm tall becomes 1.50 by 2.49 cm or 1.50 by 2.51 cm. Why?

In Draw, rectangle box of 1.50 cm wide by 2.50 cm tall becomes 1.50 by 2.49 cm or 1.50 by 2.51 cm. Why? How to fix?

He, when it happened? And what is your o.s.?
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