Answer:
[tex]3x+15[/tex]
Step-by-step explanation:
The given statement can be expressed as
[tex]3x+15[/tex]
When it says "the sum of a number three times", it refers to [tex]3x[/tex], because "times" means product.
Then, the problem specifies that the sum is between [tex]3x[/tex] and the number 15.
Therefore, the expressions is [tex]3x+15[/tex]
