Two groups of people were asked to take part in a study. The individuals in group 1 were healthy and the individuals in group 2 had recently recovered from an asthma attack.
In the experiment each individual was asked to breathe in as deeply as they could. They then breathed out via forced expiration.
A study coordinator measured the volume of air that each individual breathed out during forced expiration.
The graph below shows the results.
![oWKPJZTP_screenshot-2023-07-13-at-9-00-01-pm](https://cdn.savemyexams.com/cdn-cgi/image/f=auto,width=1920/uploads/2023/07/oWKPJZTP_screenshot-2023-07-13-at-9-00-01-pm.png)
The FEV (forced expiration volume) is the volume of air that an individual can breathe out within a single second.
Using the graph, calculate the percentage difference in the FEV for group 2 compared with group 1.