[tex]\it 2\dfrac{1}{2} = 2,5
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\{a;\ 1,5;\ 2,5\}\ d.\ p.\ \{10;\ b;\ 40\} \Rightarrow \dfrac{a}{10} = \dfrac{1,5}{b} =\dfrac{2,5}{40} \Rightarrow[/tex]
[tex]\it \Rightarrow \begin{cases}\it \dfrac{a}{10} = \dfrac{2,5}{40} \Rightarrow a = \dfrac{2,5\cdot10}{40} =\dfrac{\ 25^{(5}}{40} =\dfrac{5}{8} =0,625 \\\;\\ \\\;\\
\it\dfrac{1,5}{b} =\dfrac{2,5}{40} \Rightarrow b= \dfrac{^{10)}1,5\cdot40}{2,5} = \dfrac{15\cdot40}{125} =\dfrac{600}{25} =24 \end{cases}[/tex]