assuming you're not suppose to use a calculator to solve this,

now, start by only looking at and multiplying/dividing the "10s"



so when you multiply/divide the 10s, you get 10^-2
now look at the other numbers (4.8, 1.2,2.2)



multiply the two answers

if you're asking why you can solve it this way, its because you multiplication is commutative/associative (you can multiply numbers in any order and group them however you want and still get the same answer)