Respuesta :

Answer:

7

Step-by-step explanation:

Let the number be n.

[tex]3n+10=31[/tex]

Subtract 10 from both sides:

[tex]3n+10-10=31-10[/tex]

[tex]3n=21[/tex]

Divide both sides by 3:

[tex]\frac{3n}{3}=\frac{21}{3}[/tex]

[tex]n=7[/tex]