The second row under the axis shows z: each mark is one standard deviation from μ. Areas use an accurate normal CDF and are rounded to four places.
Sketch first, then compute. The worked solution builds line by line after a correct answer or when you ask for it.
Your jobEach picture shades part of a normal curve. Pick the percent of the area that is shaded, as fast as you can. Use the empirical rule (68, 95, 99.7) and symmetry to estimate. Keys 1 2 3 pick an answer.
Press Start to begin.
Fictional settings and practice numbers chosen to look realistic. They are not clinical reference values or advice.
Wrong picks are fine here. Each one tells you why.