Alrighty, so, if I remember correctly: For the first question you have 20 possible outcomes, 4 of which are multiples of 5. (5,10,15,20). This gives you 4/20, I multiplied both the numerator and denominator by 200 which then gave me 800/4000. Next I divided which gave me 0.2.
5578/68=82.029411764705882352941176470588
that would be rounded to 82.02 which is the answer
Answer: 
Step-by-step explanation:
The missing figure is attached.
The volume of grain that could completely fill this silo is the sum of the volume of the cylinder and the volume of the hemisphere.
By definition, the volume of a cylinder can be calculated with this formula:

Where "r" is the radius and "h" is the height.
In this case you know that:

And the volume of a hemisphere can be found using the following formula:

Where "r" is the radius.
In this case:

Therefore, the volume of grain that could completely fill this silo, rounded to the nearest whole number, is:

I hope this helps you
-2x <2x-4
4 <4x
1 <x
2x-4 <4
2x <8
x <4
1 <x <4