First, let's think about variation...The question NEVER states what direction the variation is in. If we think about a Bell curve... There are two sides to a Bell curve. Since we know the Bell curve had two sides, and the question NEVER states whether the variance is higher or lower, that would be our first question. Where is the variance? The process could be very unstable and jump on both sides.

Here's an example:

Standard deviation is very important here. For example, let's say the average is 10 and you have a 5-point variation. This variation can be in one of three scenarios:

All 5 points on the higher side which will make it 15,

All 5 points on the lower end which will make it 5,

Variation equally on both sides which will make it 7.5 to 12.5 making each side "only" 2.5 from the average.

Now I'll ask you - in which scenario would you say is cause for alarm?