The given expression is 3b x 4c
In this 3 and 4 are the coefficients and b and c are the variables.
When we multiply the coefficients we get:
3 x 4 = 12
And the product of variables is:
b x c = bc
Now multiply the product of coefficients
and product of variables we get:
12 x bc = 12bc
So 12bc is the answer.