Question

The number of minutes spent by two students, X and Y, exercising every day in a given week are shown in the bar chart above. 
The number of days in the given week in which one of the students spent a minimum of 10\% more than the other student, on a given day, is 

• A. 4
• B. 5
• C. 6
• D. 7

Hint:

To find the percentage difference in time spent, use the formula \( \left| \frac{\text{Time of X} - \text{Time of Y}}{\text{Time of Y}} \right| \times 100 \) and check if it exceeds 10\%.

Answer 1

The Correct Option is C

From the bar chart, we compare the minutes spent by students X and Y on each day. We need to find the days where one student spent at least 10% more time than the other. For each day, we calculate the percentage difference using the formula: \[ \text{Percentage Difference} = \left| \frac{\text{Minutes of X} - \text{Minutes of Y}}{\text{Minutes of Y}} \right| \times 100 \] - For Monday: \( |70 - 45| / 45 \times 100 = 55.56\% \) (X spent more)
- For Tuesday: \( |60 - 55| / 55 \times 100 = 9.09\% \) (No 10% difference)
- For Wednesday: \( |65 - 60| / 60 \times 100 = 8.33\% \) (No 10% difference)
- For Thursday: \( |60 - 55| / 55 \times 100 = 9.09\% \) (No 10% difference)
- For Friday: \( |50 - 35| / 35 \times 100 = 42.86\% \) (X spent more)
- For Saturday: \( |55 - 50| / 50 \times 100 = 10\% \) (No 10% difference)
- For Sunday: \( |65 - 55| / 55 \times 100 = 18.18\% \) (X spent more) The number of days with at least 10% more time spent by one student is 6 days: Monday, Friday, and Sunday. 
Thus, the correct answer is (C) 6. 
Final Answer: (C) 6