Answer:
45
Step-by-step explanation:
Given that the number of savory dishes is 9 and the number of sweet dished is 5.
Denoting all the 9 savory dishes by [tex]p_1, p_2,...,p_9[/tex], and all the sweet dishes by [tex]q_1,q_2,...,q_5[/tex].
The possible different mix-and-match plates consisting of two savory dishes are as follows:
There are 9 plates with [tex]q_1[/tex] from sweet plates which are [tex](q_1, p_1), (q_1, p_2), ..., (q_1,p_9).[/tex]
There are 9 plates with [tex]q_2[/tex] from sweet plates which are [tex](q_2, p_1), (q_2, p_2), ..., (q_2,p_9).[/tex]
Similarly, there are 9 plated for each [tex]q_3, q_4[/tex] and [tex]q_5.[/tex]
Hence, the total number of the different mix-and-match plates consisting of two savory dishes
[tex]= 9+9+9+9+9= 9\times5=45[/tex]