Scientific notation

Divide:

(6.9 x 10⁷) ÷ (2.3 x 10^-3)

• 3 x 10¹⁰

• 3 x 10⁴

• 3 x 10^-4

• 3 x 10^-11

Joan used the steps to calculate the quotient   $3.9\times10^8\ \div\left(1.3\times10^4\right)$  What was her error?   $3.9\times10^8\div\left(1.3\times10^4\right)\ =\frac{3.9\times10^8}{1.3\times10^4}$   $=\frac{3.9}{1.3}\times\frac{10^8}{10^4}=3.0\times10^2$  

• When dividing, Joan should have multiplied by  $10^4$  instead of dividing, and added the exponents.   $\frac{10^8}{10^4}=10^{12}$  

• When dividing powers of 10, Joan should have subtracted the exponents. $\frac{10^8}{10^4}=10^4$  

• Since both numbers are in scientific notation, Joan should have found the difference between the numbers 3.9 and 1.3.    3.9 – 1.3 = 2.6.

• Since both numbers are in scientific notation, Joan should have found the sum of the numbers 3.9 and 1.3.  3.9 +1.3 = 5.2.

You have to change the exponent when multiplying and dividing scientific notation

• True

• False

What do you do to your exponents when you are multiplying in scientific notation?

• subtract

• add

• multiply

• divide

3.4608×10⁷ ÷ 7.21×10³ = 4.8×10³

• True
• False

When multiplying in scientific notation, what do you do with the constants?

• Keep them

• Add them

• Multiply them

Solve the expression and remember to pick the answer in Scientific Notation:

 $6.3\cdot10^{-4}\div\left(9\cdot10^{-6}\right)=$  

•  $0.7\cdot10^{-10}$  

•  $7\cdot10^1$  

•  $0.7\cdot10^2$  

•  $7\cdot10^{-2}$  

 $Divide\ \ \frac{6.86\ x\ 10^{-1}}{2\ x\ 10^{-3}}$  

•  $3.43\ x\ 10^{-4}$  

•  $3.43\ x\ 10^2$  

•  $4.86\ x\ 10^2$  

•  $4.86\ x\ 10^{-4}$  

Divide: (8 x 10^-23) 
÷ (2 x 10^-25)

• 4 x 10²
• 4 x 10^-2
• 4 x 10^-48
• 6 x 10²

Divide.

(6.9 x 10⁷) / (2.3 x 10^-3)

• 3 x 10¹⁰

• 3 x 10⁴

• 3 x 10^-4

• 3 x 10^-11