Question

How many times larger is 1.8x10^-3 than 2.0x10^-5?

Answer 1

Just divide the biggest with the smallest and you'll see the ratio

1.8 x 10^(-3)/ 2.0 x 10^(-5) = 1.8 x 10^(-3 + 5)/2.0 = 0.9 x 10^2 = 90

So 1.8 x 10^(-3) is 90 times larger