Multiply by 1-digit numbers: word problems

An apartment has 4 bedrooms. Each bedroom has 3 bookcases. How many bookcases are there in the apartment?

3 × 4 = 12

There are 12 bookcases in the apartment.

Marinna was placing her coins into stacks. Each stack had 1 coins. If she had 9 stacks, how many coins did she have?