Extremly easy elementary question I need help with?

Question: Ok my brother needs help on a math question: It gives you a list on numbers in two colomns 1st Number Second Number 3--------------------8 4--------------------11 5-------------------14 6-------------------17 ... ... ... ... ... ... 10-----------------29 a. If 50 is the first number then what is the second number? b. If 200 is the first number then what is the second number? c. If 89 is the second number then what is the first number? d. If a number n is the first number then what is the second number? This depresses me I cant answer an elementary question and Im in pre-calc. Wow so can you guys help me on this problem? I WAS ON E THE RIGHT TRACK TOO! omg i feel stupider than stupid. I need like fifty bajilion hours to get over the simplicity.

Answer: The number pattern is simple. Take the first number, multiple it by 2 and then add that value to the (first number - 1) to get the second number so if 50 is the frist number, (50 x 2) + (50 - 1) = 100 + 49 = 149 so if the first number is 200, (200 x 2) + (200 - 1) = 400 + 199 = 599 if the second number is 89, you would have to work backwards. you can deduce the equation connecting the first and the second number. it should go something like this let the first number be y and the second number be z. (2 x y) + (y + 1) = z when z is 89 (2 x y) + (y - 1) = 89 2y + y -1 = 89 3y = 89 + 1 3y = 90 y = 30 so the equation connecting the two numbers in terms of n is: (2 x n) + (n -1) = second number which can be simplifed: (2 x n) + (n - 1) = second number 2n + n - 1 = second number 3n - 1 = second number (answer)

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