A scientist studied how an antibiotic affected the treatment of cholera. 320 people who had cholera were split into two groups. One group received the antibiotic, whereas the other group did not receive the antibiotic. Both groups were given fluids that contained sugars and mineral salts (oral rehydration therapy). The scientist noted the number of days each person had diarrhoea. The table below gives the results. Treatment: antibiotic and oral rehydration therapy, mean time person had diarrhoea = 3.2 days; oral rehydration therapy, mean time person had diarrhoea = 5.3 days. Calculate the percentage decrease in the mean time that a person had diarrhoea when the antibiotic was used.
- A39.6%
- B60.4%
- C165.6%
- D252.4%