Answer:
The most likely solution sought is 13:
Beginning with 3: subtract 9, add 18, subtract 8, add 16, subtract 7, add 14, etc. Each time, reduce the number subtracted by one, and double that number to add.
So, beginning with 3: 3-9 = -6, -6+2(9) = 12, 12-8 = 4, 4+2(8) = 20, 20-7 = 13, etc.
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Step-by-step explanation:
Star = 5
square =3
or the other way around
All real numbers is the correct answer.
