The sum of the first 100 positive integers is 5,050. What is the sum of the first 200 positive integers?
(A) 10,100
(B) 10,200
(C) 15,050
(D) 20,050
(E) 20,100
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Number Properties
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heshamelaziry
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mahendra700
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heshamelaziry wrote:The sum of the first 100 positive integers is 5,050. What is the sum of the first 200 positive integers?
(A) 10,100
(B) 10,200
(C) 15,050
(D) 20,050
(E) 20,100
The formula for sum of first 200 positive integers is n(n+1)/2
==> 200*201/2= 20,100
Hence E is the answer
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truplayer256
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Notice that the sum of the first 200 positive integers is...
5050+100+1+100+2+100+3....100+100
=5050+100(100)+5050=20100
E
5050+100+1+100+2+100+3....100+100
=5050+100(100)+5050=20100
E
