what is the answer to (4.1*10^3)+(3.7*10^ 2)

Using calculator may be a good method......

$(4.1\times 10^3)+(3.7\times 10^2)\\ = 4100 + 370\\ = 4470\\ = 4.47 \times 10^3$

$(4.1\times 10^3 )+(3.7\times 10^2)\\ =(41 \times 10^2)+(3.7 \times 10^2)\\ = 44.7 \times 10^2\\ = 4.47 \times 10^3$

Use a calculator 

Thanks Wong