Respuesta :

Answer:

[tex]\dfrac{-517}{504}=-1.0258[/tex]

Step-by-step explanation:

We are given an algebraic expression in two variables m and n as:

 [tex]\dfrac{1}{3m}-1-\dfrac{1}{2n}[/tex]

Now we are asked to evaluate this algebraic expression at :

m=21 and n=12

Hence, putting the values of m and n in algebraic expression we get:

[tex]\dfrac{1}{3\times 21}-1-\dfrac{1}{2\times 12}\\\\\\=\dfrac{1}{63}-1-\dfrac{1}{24}\\\\=\dfrac{-517}{504}\\\\=-1.0258[/tex]

Hence, the value of the expression is:

[tex]\dfrac{-517}{504}=-1.0258[/tex]

We have that the expression is

-1.02579365

From the Question we are told that

[tex]\frac{ 1}{3m} -1-\frac{1}{2n}[/tex]

m =21

n=12

Therefore the expression gives

[tex]\frac{ 1}{3(21)} -1-\frac{1}{2(12)}[/tex]

-1.02579365

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