For each integer n 1, let A(n) denote the sum of the integers from 1

Question

For each integer n > 1, let A(n) denote the sum of the integers from 1 to n. For example, A(100) = 1 + 2 + 3 + . . . + 100 = 5,050. What is the value of A(200)?

A. 10,100
B. 15,050
C. 15,150
D. 20,100
E. 21,500

Kavicogsci · Answer

We are asked to calculate sum of 200 consecutive integers starting from 1 and ending in 200 with both numbers inclusive

Quick formula for sum of n consecutive integers starting from 1
 /2
200*201/2
20100

Sajjad1994 · Answer

OE

In the question, you are given that A(n) is equal to the sum of the integers from 1 to n, so A(200) = 1 + 2 + 3 +...+ 100 + 101 + 102 + 103 +... + 200. In order to be able to use the given value of A(100) = 5,050, you can rewrite the sum as

Thus the correct answer is Choice D.

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For each integer n > 1, let A(n) denote the sum of the integers from 1

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