Understanding the mean graphically: Two bars
ALEKS shows two black bars of different heights and asks you to drag a light bar until its height equals their mean. The arithmetic is dead simple — average the two heights — but the picture reinforces the "balance" intuition: the mean sits exactly halfway between two values.
A short walkthrough explaining what you need to know and how to solve this question type lands here once it's recorded.
ALEKS randomizes the numbers each attempt, but the question shape stays the same. Here are three example versions you might see.
The graph below shows two black bars. Adjust the light bar so that it has the mean height of the two black bars.
Visual prompt: ALEKS shows two black bars at heights of, for example, 8 and 4. Drag the light bar's top until it sits at the midpoint of the two black bars.
Two black bars are shown at heights 10 and 6. Adjust the light bar so its height equals the mean of the two black bars.
Two black bars are shown at heights 7 and 3. Adjust the light bar to the mean height.
Read both bar heights.
Say the two black bars sit at heights b₁ = 8 and b₂ = 4 (use the y-axis gridlines to estimate).
Compute the mean.
The mean is 6 — exactly halfway between 4 and 8. Visually, the light bar's top should land on the dashed midline.
Drag the light bar to that height.
On ALEKS, click and drag the top edge of the light bar until it sits at the computed mean. The tool snaps to gridlines, so reading the y-axis carefully in step 1 makes step 3 trivial.
Practice with two different bar heights. The mean always sits at the midpoint.
Compute the mean of two bars.
Now with smaller bars.
You've walked through the whole problem.
That's the move. ALEKS will give you a different version with different numbers — but the steps are the same.