What is the answer to 3x10 to the power of 4 plus 2.5x10 to the power of 5 equal to?

Answer 1

You need to

• express them both in the same power
• sum them
• express in the appropriate power.

So 3*104 + 2.5*105 = 3*104 + 25*104 = 28*104 = 2.8*105

or

So 3*104 + 2.5*105 = 0.3*105 + 2.5*105 = 2.8*105