Simplify the expression...

Question

Simplify the expression. Express the answer in scientific notation.

 

(2.1 × 10⁴) + (7.4 × 10⁶)

Answer 1

make the 10's exponents equal before adding

2.1 x 10^4 = .021 x 10^6, increase the exponent by 2 means compensate by moving decimal point left twice

Now add that to 7.4 x 10^6

.021 x 10^6

to get 7.421 x 10^6

IF you round to one decimal place, that's 7.4 x 10^6