Evaluate the expression. Write your answer in scientific notation.(9×10^−3)+(2.4×10^−5) ÷ 0.0012The answer is 2.9 times 10^-2 I just don't know how to get that.

We are given this expression:
[tex](9*10^{-3})+(2.4*10^{-5})\div.0012[/tex]Let's first evaluate 9 * 10^(-3) by moving the decimal place of 9 to the left 3 times.
[tex]9*10^{-3}=.009[/tex]Now, let's evaluate 2.4 * 10^(-5) by moving the decimal place of 2.4 to the left 5 times.
[tex].000024[/tex]Now, we have this expression:
[tex].009+.000024\div.0012[/tex]Start by dividing .000024 and .0012 because we must divide before adding.
Now, we have this expression:
[tex].009+.02[/tex]Add these terms together to get:
[tex].029[/tex]This number, .029 in scientific notation, is 2.9 * 10^(-2) since if we move the decimal place to the left in 2.9 two times, we get .029.