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The question for the day is a Math question from the topic Arithmetic Mean.

Question 2

The arithmetic mean of the 5 consecutive integers starting with 's' is 'a'. What is the arithmetic mean of 9 consecutive integers that start with s + 2?

1. 2 + s + a
2. 2 + a
3. 2s
4. 2a + 2
5. 4 + a

The correct choice is (E) and the correct answer is 4 + a.

Explanatory Answer

The fastest way to solve such questions is to assume a value for 's'.

Let s be 1.

Therefore, the 5 consecutive integers that start with 1 are 1, 2, 3, 4 and 5.

The average of these 5 numbers is 3.

9 consecutive integers that start with 1 + 2 are 3, 4, 5, 6, 7, 8, 9, 10 and 11

The average of these 9 number is 7.

Now, let us take a look at the answer choices and substitute '1' for 's' and '3' for 'a'.

The only choice that provides us with an answer of '7' is choice (E).

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