25 writers, 20 doctors, 18 dentists and 12 bank employees spent altogether ₹ 1,330 in a hotel. However, it was found that 5 writers spent as much as 4 doctors, that 12 doctors spent as much as 9 dentists, and that 6 dentists spent as much as 8 bank employees. Out of the four professional groups, which group spent the maximum amount ?

Let w, d, t, and b represent the individual expenditure of a writer, doctor, dentist, and bank employee respectively. From the given conditions:

• 5w = 4d → w = 4/5 d
• 12d = 9t → t = 12/9 d = 4/3 d
• 6t = 8b → b = 6/8 t = 3/4 t = 3/4 × (4/3 d) = 1d

Now, calculate the total expenditure for each professional group:

• Writers: 25w = 25 × (4/5 d) = 20d
• Doctors: 20d
• Dentists: 18t = 18 × (4/3 d) = 24d
• Bank employees: 12b = 12 × (1d) = 12d

Comparing the total amounts (20d, 20d, 24d, and 12d), the Dentists group spent the maximum amount.