Answer:
For 135 students , the number of teacher requires is 9
Step-by-step explanation:
Given as :
The number of teacher = 6
The number of student  = 90
∵   For 90 students , the number of teacher requires = 6
So , For 1 student , the number of teacher requires = [tex]\frac{6}{90}[/tex]
                                           = [tex]\frac{1}{15}[/tex]
∴  For 135 student , the number of teacher requires =  [tex]\frac{1}{15}[/tex]×135
Or, For 135 student , the number of teacher requires = Â [tex]\frac{135}{15}[/tex]
So, For 135 student , the number of teacher requires = 9
Hence For 135 students , the number of teacher requires is 9 Â Answer