Which description matches the algebraic expression 45n a. the sum of a number and 45 b. the quotient of a number and 45 c. the product of a number and 45 d. the difference of a number and 45

 The correct description is (C). the product of a number and 45.

Step-by-step explanation:  We are given to select the correct description that matches the algebraic expression 45n.

Let, 'n' be a number.

Then, the sum of 'n' and 45 is written as (45 + n).

So, option (A) is incorrect.

The quotient of 'n' and 45 is given by

So, option (B) is incorrect.

The product of 'n' and 45 is

45 × n = 45n, which means 45 times of a number 'n' or n times of 45.

So, option (C) is correct.

The difference of 'n' and 45 is (n - 45) or (45 - n), according as 'n' is greater or 45 is greater.

So, option (D) is incorrect.

Thus, the correct option is (C).