A camera offers many different modes that can be useful.  I will not go through all of them because I just do not care.

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What interest me are the Aperture, Speed and ISO mode.

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You really need to pay attention to your camera settings.

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If you use the Aperture mode you think you have only Speed as a variable, well, you are wrong if you have not set the ISO, same goes for the speed and manual here is why:

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• Aperture mode = 1/3 of the EV value.  Speed and ISO are variables
• Speed mode = 1/3 of the EV value.  Aperture and ISO are variables
• Manual mode = Aperture and and Speed create 2/3 of the EV value.  ISO is a variable. 

If you fix the ISO

• Aperture mode, Aperture and ISO are absolute 2/3 of the EV value, Speed is the variable.
• Speed mode, Speed and ISO are absolute 2/3 of the EV value, Aperture is the variable.
• Manual mode, Aperture, Speed and ISO are absolute.

This makes the EV table outdated as it was created using only one ISO value (100).  Now to know the right EV value you must slide the table up or down depending on your ISO value and even that is not really correct.