The median of a distribution can be estimated from

Analyze the question: The question asks which graph or chart can be used to estimate the median of a distribution.

Explain the concept:

• The median is the middle value of an ordered data set. Half of the values lie below it and half lie above it.
• The cumulative frequency curve (ogive) plots running totals of frequency against the class boundaries. It is built to show how many observations fall below a given value.

Step-by-step solution:

1. Take the total frequency, N, from the last point on the cumulative frequency axis.
2. Find N/2 on the cumulative frequency axis.
3. Draw a horizontal line from N/2 across to the curve.
4. From that point on the curve, draw a vertical line down to the x-axis.
5. The value where it meets the x-axis is the estimated median.

Why the other options don't work:

• Bar chart: it compares frequencies of categories. It is used to find the mode (the tallest bar), not the median.
• Frequency polygon: it shows the shape of the distribution and can suggest the modal class, but it cannot give the median directly.
• Pictorial (pictogram): it uses symbols to represent data, so it is not suitable for locating the median.
• Pie chart: it shows proportions of a whole, not the middle value.

Answer: B. Cumulative frequency curve.

Exam tip: Remember these pairings:

• Mode comes from a histogram or bar chart.
• Median and quartiles come from the ogive (cumulative frequency curve).
• Mean comes from calculation.

Whenever you see "median", "quartiles" or "percentiles" in a graph question, think ogive.