question_answer

The number machine shown uses a rule to change each number that is put into it to a different number. The same rule is used every time. The table given shows the results when three different numbers were put into the number machine.

In	Out
8	20
5	14
12	18

Which of the following could be the rule used by the number machine?

A)  Add 12

B)  Add 24

C)  Multiply by 2, then add 4 to the result.

D)  Multiply by 3, then subtract 4 from the result.