ANSWER
The number of children between the ages of 9 and 15 who visited the park is
EXPLANATION
The number of children between the ages of 9 and 15 who visited the park are those within the age group 9 to 12 and 12 to 15.
We can from the graph that, the height of the bar that corresponds to the age group 9 to 12
and the height of the bar that corresponds to the age group 12 to 15
The sum of the two frequencies
The number of children between the ages of 9 and 15 who visited the park is
EXPLANATION
The number of children between the ages of 9 and 15 who visited the park are those within the age group 9 to 12 and 12 to 15.
We can from the graph that, the height of the bar that corresponds to the age group 9 to 12
and the height of the bar that corresponds to the age group 12 to 15
The sum of the two frequencies