Answer:
12 adults 
Explanation:
Given that :
Let :
Number of children = x
Number of adult = y
x = 32 + y - - - - - (1)
Ratio of adult to children 
3 : 11
x = (11/3)y - - - (2)
Put x = 11/3y in (1)
(11/3)y = 32 + y 
11y/3 - y = 32
(11y - 3y) / 3 = 32 
11y - 3y = 32 * 3 
8y = 96
y = 96/8
y = 12
Hence, number of adults = 12