1. Mathematical Operations Using Numbers in Scientific Notation

2. Adding All numbers must be expressed in the same power of 10
(A x 10m) + (B x 10m)  (A + B) x 10m
(1.234 x 10‾³) + (5.623 x 10‾3) =
1.234
6.857 = x 10‾3 (answer is in correct sig figs)

3. Adding All numbers must be expressed in the same power of 10
(A x 10m) + (B x 10m)  (A + B) x 10m
(2.2 x 10³) + (4.12 x 103) =
Line up the decimals and add
2.2 x 10³
x 103
6.32 x 103 = 6.3 x 103 (round to correct sig figs)

4. When moving decimals: If you move the decimal to the right, add (-1) to the exponent If you move the decimal to the left, add (+1) to the exponent

5. 10.85 X 10-2 need to move the decimal to the left so will add a (+1) = X = X 10-1 If your result is: x 102 need to move the decimal to the right so will add a (-1) = x = 2.33 X 101

6. 1.234 Different Exponents (1.234 x 10‾³) + (5.623 x 10‾²) =
Doesn’t matter which exponent you change
(1.234 x 10‾³) + (56.23 x =-3) = x 10‾²
1.234
+56.23
x 10‾³ = x 10‾³
= x 10‾²
( x 10‾²) + (5.623 x 10‾²) = x 10‾²

7. Addition
( x 10‾2) + (5.623 x 10‾²) =
Doesn’t matter which exponent you change
( x 10‾²) + (5.623 x 10‾²) = x 10‾2
= x 10‾2 OR
(1.234 x 10‾³) - (56.23 x =-3) = x 10‾²
1.234
x 10‾³ = x 10‾²

8. Check your work! (1.234 x 10‾³) + (5.623 x 10‾²) ==
= x 10‾²

9. Subtracting
2000 X 104 – 5 X 104 = 1995 X 104 Need to round answer to correct sig figs! 1995 X 104 becomes 2000 X 104 Still not done! 2000 X 104 = move the decimal 3 places to the left and add “3” to the exponent 2000 X = 2 x 107

10. Multiplying Multiply the decimal parts Add the exponents of 10s
(A x 10m) x (B x 10n)  (A x B) x 10(m +n)
(1.23 x 103) x (7.60 x 102) =
(1.23 x 7.60) x 10 (3 + 2)
= x 10 5
= x 10 5
(ROUND TO CORRECT SIG FIGS)

11. Example
(4.16 x 103)(2 x 104) =

12. Dividing Divide the decimal parts Subtract the exponents
(A x 10x)  (B x 10y)  (A  B) x 10(x-y) or A B
10(x-y) x

13. Example:
(4.68 x 10-3) ÷ (4.00 x 10-5)
4.68
4.00
10 -3-(-5) = 1.17 x 102 x

14. Using Pre-determined Measurements in Calculations The value given in your calculation will influence the number of sig figs in your answer.

15. Page 90 - Classroom exercises