A square picture with a side length of 30 cm is scaled by 60% on a photocopier. The copy is then scaled by 60% again. What is the side length of the picture after it has been successively scaled by 60% 4 times?

10.8 cm

Step-by-step explanation:
we know that
1) A square picture with side length 30 cm is scaled by 60% on a photocopier
Remember that
60% =60/100 = .60

so The length of the first copy of the picture is
30(.60) = 18

2) The copy is then scaled by 60% again
so
The length of the second copy of the picture is
18(.60)=10.8 cm