2 cm x 4.5 cm at 200 dpi is equivalent to 158 x 354 pixels.
Explanation:
The given dimensions are 2 cm x 4.5 cm
Since, 1 inch is equal to 2.54 cm
(2/2.54)=0.79
(4.5/2.54)=1.77
2 cm x 4.5 cm is equal to 0.79 in x 1.77 in
Now, the given dpi (dots per inch or pixels per inches) is 200 that means there are 200 dots or pixels in 1 inch
Hence, the dimensions in pixels will be 0.79 x 200 x 1.77 x 200 pixels =158 x 354 pixels.