how do I simplify (1.9 × 1010) + (3.7 × 109)

(1.9 × 1010) + (3.7 × 109)

I suspect that this is what you are really after     ^  means 'to the power of'

(1.9 × 10^10) + (3.7 × 10^9)

You can put it straight into the site calc OR

 

=(1.9 × 10 ×10^9) + (3.7 × 10^9)

=(19 ×10^9) + (3.7 × 10^9)

= (19+3.7)×10^9

=22.7×10^9

=2.27×10×10^9

=2.27× 10^10