Question

Alifa scores an aggregate of 60% marks in the Five subjects in her Class 8 Year end Examination. Her marks are in the ratio 10:9:8:7:6. If the passing marks are 50% of the maximum marks and each subject has the same maximum marks, in how many subjects did Alifa pass the Examination?

• A. 1
• B. 2
• C. 3
• D. 4
• E. 5

Hint:

Find the marks per subject using the ratio and total marks, then compare with passing marks.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
Find the individual percentages of marks in each subject based on the total average and the given ratio.
Step 2: Key Formula or Approach:
Subject Percentage = (Total % \(\times\) Total Subjects) \(\times\) (Ratio Part / Ratio Sum).
Step 3: Detailed Explanation:
1. Total aggregate % = 60%. For 5 subjects, total units = \(60 \times 5 = 300\). 2. Ratio sum = \(10 + 9 + 8 + 7 + 6 = 40\). 3. Value of one unit of ratio = \(300 / 40 = 7.5\). 4. Marks in each subject (%): - Sub 1: \(10 \times 7.5 = 75%\) - Sub 2: \(9 \times 7.5 = 67.5%\) - Sub 3: \(8 \times 7.5 = 60%\) - Sub 4: \(7 \times 7.5 = 52.5%\) - Sub 5: \(6 \times 7.5 = 45%\) 5. Passing criteria is 50%. 6. Alifa scored \(\ge 50%\) in 4 subjects (75, 67.5, 60, 52.5).
Step 4: Final Answer:
Alifa passed in 4 subjects.