Addition and Subtraction (Exponential Notation)

Step 1 - add/subtract the decimal

Step 2 – Bring down the given exponent on the 10

When adding or subtracting numbers in scientific notation, the exponents must be the same.

If they are different, you must move the decimal so that they will have the same exponent.

Step 1 – Rewrite so the exponents are the same 

Step 2 - add/subtract the decimal

Step 3 – Bring down the given exponent on the 10

 $\left(5.7×10^8\right)+\left(1.27×10^9\right)$ 

 $\left(0.57\times10^9\right)+\left(1.27\times10^9\right)$  

 $\left(0.57+1.27\right)=1.84$  

 $1.84\times10^9$  

 $\left(5.7×10^8\right)+\left(1.27×10^9\right)$ 

 $\left(5.7\times10^8\right)+\left(12.7\times10^8\right)$  

 $\left(5.7+12.7\right)=18.4$  

 $18.4\times10^8$  

 $1.84\times10^9$