[tex]We \: \: \: \: know \\ mean \: \: = \frac{sum \: \: \: of \: \: \: the \: \: \: terms}{number \: \: \: of \: \: \: terms} \\ [/tex]
[tex]Given \: \: \: here \: \: the \: \: \: mean \\ of \: \: \: 3y + 1 \: \: \: and \: \: \: 4y + 9 \: \: \: is \: \: \: 2y + 11.[/tex]
[tex]Therefore \\ \frac{(3y + 1) + (4y + 9)}{2} = 2y + 11 \\ = > \frac{7y + 10}{2} = 2y + 11 \\ = > 7y + 10 = 2(2y + 11) \\ = > 7y + 10 = 4y + 22 \\ = > 7y - 4y = 22 - 10 \\ = > 3y = 12 \\ = > y = \frac{12}{3} \\ = > y = 4[/tex]
[tex]Your \: \: \: answer \: \: \: is \: \: \: 4.[/tex]
