Directions: A survey of magazine reading habits of the people living in five cities P, Q, R, S and T is summarised in a table given below. The Column I in the table gives percentage of magazine-readers in each city who read only one magazine a week. The Column II gives the total number of magazine-readers who read two or more magazines a week. Read the table and then answer these questions: | City | I | II | | :--- | :---: | :---: | | P | 75 | 6000 | | Q | 80 | 3500 | | R | 60 | 3000 | | S | 55 | 2700 | | T | 25 | 4200 | The total number of all the magazine-readers in the five cities who read only one magazine a week is

### Concept & Logic To find the grand total of single-magazine readers across all cities, we must calculate the absolute number of these readers for each city individually and then sum them up. $$ \text{Single Readers} = \text{Total Readers} - \text{Readers of } 2+ $$ $$ \text{Total Single Readers} = \sum (\text{Single Readers per City}) $$ ### Step-by-Step Solution Let's calculate the "only one magazine" readers for each city. We do this by finding total readers first (or using the direct ratio multiplier). * **City P:** Total = $\frac{6000}{0.25} = 24000$. Single readers = $24000 - 6000 = 18000$. * **City Q:** Total = $\frac{3500}{0.20} = 17500$. Single readers = $17500 - 3500 = 14000$. * **City R:** Total = $\frac{3000}{0.40} = 7500$. Single readers = $7500 - 3000 = 4500$. * **City S:** Total = $\frac{2700}{0.45} = 6000$. Single readers = $6000 - 2700 = 3300$. * **City T:** Total = $\frac{4200}{0.75} = 5600$. Single readers = $5600 - 4200 = 1400$. Now, sum these calculated values together: $$ \text{Grand Total} = 18000 + 14000 + 4500 + 3300 + 1400 $$ $$ \text{Grand Total} = 32000 + 4500 + 3300 + 1400 $$ $$ \text{Grand Total} = 36500 + 3300 + 1400 $$ $$ \text{Grand Total} = 39800 + 1400 = 41200 $$ ### Exam Strategy & Shortcut **Leverage Previous Work:** In a grouped data set like this, always write down your intermediate values clearly in a table format on your scratchpad. You should have already calculated the totals and sub-categories in previous questions (like Q175). Just retrieve the list: $18000, 14000, 4500, 3300, 1400$. Summing them mentally using place value: Thousands: $18 + 14 + 4 + 3 + 1 = 40$ thousand. Hundreds: $0 + 0 + 500 + 300 + 400 = 1200$. Total: $40000 + 1200 = 41200$. ### Common Pitfall A severe mistake is summing the percentages in Column I or summing the numbers in Column II and attempting a single global calculation. Percentages from different base totals cannot be added together directly. Each city must be processed individually. ### Final Answer **Therefore, the correct answer is 41200.**