Translate the sentence into an equation. Twice the difference of a number and 4 is equal to 9.
Use the variable w for the unknown number.

2(w-4)=9

Step-by-step explanation:

Twice the difference between a number and 4 means 2 will be multiplied to both w and 4. Then the equation is equal to 9.

if you are saying purchasing 3 social media ads and one newspaper ad counts as one purchase then there are:

6 purchases

if you are asking how many of each then:

18 social media ads

6 newspaper ads