Correct Answer - Option 3 : 19, 38
Given:
Average price of 16 books = Rs. 18
Average price of 14 books = Rs. 16.50
Price of one of remaining book = 50% of price of another remaining book
Concept used:
Average = Total sum of observation/Number of observations
Calculation:
As we know that
Average = Total sum of observation/Number of observations
Total price of 16 books = Rs. 18 × 16
⇒ Rs. 288
Total price of 14 books = Rs. 16.50 × 14
⇒ Rs. 231
Total Price of remaining books = Total price of 16 books - Total price of 14 books
⇒ Rs. (288 - 231)
⇒ Rs. 57
Now, Let the price of one of remaining book be x
Price of another remaining book = 50% of x
⇒ x/2
According to the question
x + (x/2) = Rs. 57
⇒ 3x/2 = 57
⇒ x = (57 × 2)/3
⇒ x = Rs. 38
Price of another remaining book = 38/2
⇒ Rs. 19
∴ The prices of books are Rs. 19 and Rs. 38.