The correct option is D 45
The decimal value written on the gray box is 0.8.
To convert this decimal into a fraction, we will remove the decimal point and divide the denominator with 10.
⟹0.8=810
Let's convert the fraction into its simplest form.
⟹810 = 8÷210÷2 =45
Hence, we can represent 0.8 as 45.