Part A of the problem asks for the mode/modes or most frequently occurring value from all the data. The most commonly occurring value is 2 bedrooms, the value that 'reaches the highest' on the bar graph.
Part B is slightly more complicated. This asks for the most common number of bedrooms for detached houses. We can answer this by looking for the frequency of the number of bedrooms for each bar.
Examining the graph tells us that the number of detached houses with 1 bedroom is 10, the number of detached homes with 2 bedrooms is 30, the number of detached houses with 3 bedrooms is 10, and the number of detached houses with 4 bedrooms is 30. Since we have two data points with the same highest frequency, we have two modes,
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