Sig Figs, Scientific Notation and Conversions

More Sig Figs, and Scientific Notation Hopefully, this is starting to make sense but let’s make sure…

1. Which of the following is the best answer to 12 x 12 = ? A. 1 x 102

B. 1.4 x 102

C. 144

D. 144.0

2. Which of the following is the best answer to 9.1 x 15 = ? A. 1 x 102

B. 1.35 x 102

C. 1.4 x 102

D. 135

3. Which of the following is the best answer to 5,460 ÷ 39 = ? A. 1 x 102

B. 1.4 x 102

C. 144

D. 144.0

4. What is the relationship between the answers to all three of the above questions? Pretty interesting, right?

5. 3.14 represents “π to ______sig figs.”

6. π + 27 =

7. 1 x 2.456723189468238979874924 = (Don’t use your calculator!) Let’s look at addition and subtraction:

8. 145 lbs – 3.0 lbs = (Hint: Line up the decimal places like you did in elementary school)

9. 145 lbs – 0.4 lbs =

10. The Earth has a mass of 6.0 x 1024 kg. A 0.25 kg chinchilla is born. What is the new, total mass of the Earth/chinchilla system?

11. There are about 200 billion stars in our galaxy. One goes out. How many stars are left?