Answer:
24
Explanation:
Sara's number is 24. The first number you can find is the number that -6 can be multiplied to to become -66, or -6 x ? = -66. The answer to this is positive 11. Since it says the difference, or 11, comes from substracting 13 from her actual number, you would add 13 to 11, which gives you 24. I hope this helps :D