Problem:

Range A1:C5 contains numbers and text.
We want to count the number of cells within that range that contain text.

Solution 1:
Use the COUNTA and COUNT functions as shown in the following formula:
=COUNTA(A1:C5)-COUNT(A1:C5)

Solution 2:
Use the COUNTIF function as shown in the following formula:
=COUNTIF(A1:C5,\"*\")