Average credit score of certain number of graduate students is 400. If

1.	Average credit score of certain number of graduate students is 400. If the average score of 4 junior students is 600 and average score of senior graduates is 200, find the number of senior graduates.1. 82. 43. 94. 12
Answer» Correct Answer - Option 2 : 4 Given: The average credit score of certain number of graduate students = 400. The average score of 4 junior students = 600 The average score of senior graduates = 200. Concepts used: Average credit score = (Sum of credit scores of graduates)/(Number of graduates) Calculation: Let the total number of graduates be x. So, the sum of credit scores of graduates = 400x Now, the sum of credit scores of junior graduates = 600 × 4 = 2,400 Number of senior graduates = x – 4 According to the question Sum of credit scores of senior graduates = 200 × (x – 4) = 200x – 800 Sum of credit scores of graduates = Sum of credit scores of graduates + Sum of credit scores of graduates ⇒ 400x = 2,400 + 200x – 800 ⇒ 400x – 200x = 1,600 ⇒ 200x = 1,600 ⇒ x = 1,600/200 = 8 Number of senior graduates = x – 4 = 8 – 4 = 4 graduates ∴ There are 4 senior graduates.

Average credit score of certain number of graduate students is 400. If the average score of 4 junior students is 600 and average score of senior graduates is 200, find the number of senior graduates.1. 82. 43. 94. 12

Answer» Correct Answer - Option 2 : 4

Given:

The average credit score of certain number of graduate students = 400.

The average score of 4 junior students = 600

The average score of senior graduates = 200.

Concepts used:

Average credit score = (Sum of credit scores of graduates)/(Number of graduates)

Calculation:

Let the total number of graduates be x.

So, the sum of credit scores of graduates = 400x

Now, the sum of credit scores of junior graduates = 600 × 4 = 2,400

Number of senior graduates = x – 4

According to the question

Sum of credit scores of senior graduates = 200 × (x – 4) = 200x – 800

Sum of credit scores of graduates = Sum of credit scores of graduates + Sum of credit scores of graduates

⇒ 400x = 2,400 + 200x – 800

⇒ 400x – 200x = 1,600

⇒ 200x = 1,600

⇒ x = 1,600/200 = 8

Number of senior graduates = x – 4 = 8 – 4 = 4 graduates

∴ There are 4 senior graduates.