Histograms and grouped data

Multiply each interval midpoint by its frequency. Add the products and divide by the total frequency: mean ≈ (5f1 + 15f2 + 25f3)/(f1 + f2 + f3). Round the final result to the precision of the choices.

Cumulative frequency up to the given bound is the sum of interval frequencies up to that bound. Start with the first interval and add in order; exclude later intervals.

Multiply each interval midpoint by its frequency. Add the products and divide by the total frequency: mean ≈ (5f1 + 15f2 + 25f3)/(f1 + f2 + f3). Round the final result to the precision of the choices.

With equal interval widths, the tallest histogram bar gives the greatest frequency. Select the interval beneath that bar.

Add the frequencies of all histogram intervals. Their sum is the total number of observations, not the number of intervals.

Read the frequencies of both specified intervals from the vertical scale. Subtract the second frequency from the first. Horizontal interval bounds are not frequencies.

All four interval frequencies sum to the total. The missing frequency is x = total − a − b − c.

Relative frequency percentage = interval frequency ÷ total frequency × 100. For example, 6 out of 20 is 30%.

Relative frequency percentage = interval frequency ÷ total frequency × 100. For example, 6 out of 20 is 30%.

A histogram shows numerical data grouped into intervals. Bars for neighbouring intervals touch, and frequencies count observations in each interval.