Let the number of guests at the wedding be represented by "g"
The number of people who take beef = 1/3*g = g/3
The number of people who opt for chicken = 5/12*g = 5g/12
The number of people who opt for vegetarian = 23
So, g/3 + 5g/12 + 23 = g since "g" is the total guests
Now,we need to solve for g
g/3 + 5g/12 + 23 = g
g-g/3-5g/12 = 23
(12g-4g-5g)/12 = 23
3g = 276
g = 276/3
g = 92
Total number of guests at the wedding = 92