Answer: Choice C) Output = 2*Input + 1
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Let's go through the choices one by one. The idea is that we replace each "input" with the number given in the table, and it should correspond to the proper output value in the same given table.
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Choice A says we add 3 to the input, so if the input is 2, then input+3 = 2+3 = 5 is the output. This matches with the first output shown. However, if the input is 4, then input+3 = 4+3 = 7 and it doesn't match with the second output 9.
So choice A is crossed off the list.
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Choice B)
Replace "input" with 2, which is the first input value listed
Output = 3*Input - 1
Output = 3*2 - 1
Output = 6 - 1
Output = 5
This matches with the first output
Now replace "input" with 4 and repeat the same steps above
Output = 3*Input - 1
Output = 3*4 - 1
Output = 12 - 1
Output = 11
This doesn't match with the 9 shown as the second output. Cross choice B off the list.
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Choice C)
Plug in input = 2
Output = 2*Input + 1
Output = 2*2 + 1 .... replace 'input' with 2
Output = 4 + 1
Output = 5 ... works
Repeat for input = 4
Output = 2*Input + 1
Output = 2*4 + 1
Output = 8 + 1
Output = 9 ... works
Repeat for input = 6
Output = 2*Input + 1
Output = 2*6 + 1
Output = 12 + 1
Output = 13 ... works
Repeat for input = 10
Output = 2*Input + 1
Output = 2*10 + 1
Output = 20 + 1
Output = 21 ... works
Each input produces the proper output as shown in the given table. So that's why choice C is the answer
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Choice D)
Output = Input + 5
Output = 2 + 5
Output = 7
The input 2 leads to the output 7, but the table shows 5 as the output we want. So choice D is crossed off the list.
