A hungry Emperor penguin was swimming 21 feet below sea level. It swam up 9 feet to eat a fish. What is the position of the penguin now relative to sea level?

Step-by-step explanation:

21 feet below is written as -21

9 feet up is written as +9

So we have -21 + 9 = -12 or 12 feet below sea level

Um, the answer is 12 feet below sea level?

Step-by-step explanation:

the mistake in the pattern is that :

b. the decimal point was moved one too many place values each time

the correct pattern could be made by :

b. moving the decimal point to the right the same numbers of place values as the exponents