Answer:
Read the explanation!
Step-by-step explanation:
<em>Let the "certain number" be </em>
<em>. </em>
(
is a symbol for multiplication).
<em>Create a few equations and expressions:</em>
The sum of 12 and a certain number: 
The product of 3 and the number: 
The sum of 12 and a certain number is equal to the product of 3 and the number:
= 
Solve!
12=3x-x
12=2x
x=6
Answer:
1.1
Step-by-step explanation:
Answer:
30
Step-by-step explanation:
Each 1 biography has 5 possible mystery novels to choose from so, for each 6 books you could choose out of 5 possible mystery books and with that being said, 5 × 6 = 30
Answer:
yes
Step-by-step explanation: