Solve (38x10 to the negative fourth power) + (4.000x10 to the negative second power

38*10^ (-4) = 0.0038

This means you move the decimal to the left (divided by 10) four times.

4.0*10^ (-2) = 0.04

This means you move the decimal to the left two times. Now add the two.

0.0038+0.04

Always line up decimals when adding them!

The final answer is 0.0438