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In a certain exam, A got 33.33% of the total marks of 300. B's marks are one fourth more than A's marks. C
got 15 marks less than B. D got 20 marks more than the average marks of A, B and C. How many among A, B,
C and D got more than 40% of the total marks?
A.
C. 2
NO
0
B.
D.
1
3

Respuesta :

Let's break down the problem step by step:

1. A got \(33.33\%\) of the total marks of \(300\), which is \(0.3333 \times 300 = 100\) marks.

2. B's marks are one fourth more than A's marks. So, B got \(100 + \frac{1}{4} \times 100 = 125\) marks.

3. C got \(15\) marks less than B, which means C got \(125 - 15 = 110\) marks.

4. D got \(20\) marks more than the average marks of A, B, and C. First, let's find the average marks of A, B, and C:

  \[ \text{Average marks} = \frac{(100 + 125 + 110)}{3} = \frac{335}{3} \]

  Now, D got \(20\) marks more than this average, which is:

  \[ \text{D's marks} = \frac{335}{3} + 20 \]

Now, let's calculate D's marks:

\[ \text{D's marks} = \frac{335}{3} + 20 = \frac{335 + 60}{3} = \frac{395}{3} \approx 131.67 \text{ marks} \]

Now, we need to determine how many among A, B, C, and D got more than \(40\%\) of the total marks.

The total marks are \(300\).

40% of \(300\) is \(0.4 \times 300 = 120\) marks.

From our calculations:

- A got \(100\) marks

- B got \(125\) marks

- C got \(110\) marks

- D got approximately \(131.67\) marks

So, B, C, and D got more than \(40\%\) of the total marks. Therefore, the answer is \( \boxed{3} \).

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