9514 1404 393
Explanation:
If you can't operate a calculator, perhaps you can do long division. The attachment shows the work for that.
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[tex]\dfrac{20}{8}=\dfrac{5\cdot4}{2\cdot4}=\dfrac{5}{2}\\\\=\dfrac{5\cdot5}{2\cdot5}=\dfrac{25}{10}=2.5[/tex]
We assume that you know dividing by 10 moves the decimal point one place left.
