A nurse measured the blood pressure of each person who visited her clinic. Following is a relative-frequency histogram for the systolic blood pressure readings for those people aged between 25 and 40 years. The blood
Pressure readings were given to the nearest whole number. Approximately what percentage of the people aged
25-40 had a systolic blood pressure reading between 110 and 119 mm Hg inclusive?
A) 0.35%
B) 30%
C) 35%
D) 3.5%

Question

A nurse measured the blood pressure of each person who visited her clinic. Following is a relative-frequency histogram for the systolic blood pressure readings for those people aged between 25 and 40 years. The blood
Pressure readings were given to the nearest whole number. Approximately what percentage of the people aged
25-40 had a systolic blood pressure reading between 110 and 119 mm Hg inclusive? 
A) 0.35% 
B) 30% 
C) 35% 
D) 3.5%

Quizplus · Accepted Answer

The relative frequency of the histogram shows the proportion of individuals with a specific range of blood pressure. To find the approximate percentage of people aged 25-40 with systolic blood pressure readings between 110 and 119 mm Hg inclusive, we need to sum up the relative frequencies of the bars in that range. This includes the bars with a lower limit of 110 up to and including the bar with an upper limit of 119. Looking at the histogram, we see that this corresponds to a total relative frequency of approximately 0.35 + 0.00 + 0.00 + 0.00 = 0.35 or 35%. Therefore, the answer is C.

A Nurse Measured the Blood Pressure of Each Person Who