



 
Hi Cheryl, Sometimes before we can find a formula, we need to find the pattern from getting to the second number given the first. Let me guide you through my though process as to how I came up with the answer: First, I try to see what the difference (subtraction) or quotient (division) is between the numbers:
In this case, the quotients don't help me so I'll ignore them. I do notice that an odd number is added to each of the first numbers to yield the second number (e.g. 3+5=8). So I need to think: "How can I make the odd number using the first number?" If multiply 3 by 2, it will yield 6 which is close to 5. If I subtract 6 by 1 then I will have 5. So to put this in formula terms, if my first number is n then I would be adding 2n1 to yield the second number: n+2n1=3n1 Now let's check to make sure that this formula works for all of the first numbers:
The formula appears to work so we can assume it will work for all numbers. There are many ways that you could have arrived at the result but sometimes if you cannot see the pattern you just have to "play" with the numbers a bit until you find something that works. Hope this helps,  


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