The sum of five consecutive integers is 35. How many of the five conse

Question

The sum of five consecutive integers is 35. How many of the five consecutive integers are prime numbers?

(A) 0
(B) 1
(C) 2
(D) 3
(E) 4

gvij2017 · Answer

n+n+1+n+2+n+3+n+4= 35
n=5. 
Two prime numbers out of 5. 
C is correct.

LeoN88 · Answer

n is not 5 but 7.

Let the numbers be, n, n+1, n-1, n+2 and n-2; adding them we get=> n*5=35, so n is 7,

Numbers: 7,8,6,9,5; Primes: 5 and 7.

Palladin · Answer

Let the five consecutive integers be  (n-2) ,  (n-1) ,  n ,  (n+1) ,  (n+2) .

Sum of the five consecutive integers is 35
 \implies (n-2) + (n-1) + n + (n+1) + (n+2) = 35 
 \implies n = 7 
 \implies  The five consecutive numbers are  5 ,  6 ,  7 ,  8 ,  9 .

There are two prime numbers,  5  and  7 , among them.
Answer is  C .

Kinshook · Answer

Both approaches are correct and yield the same result

First Approach: - 
If we assume numbers as n, n+1, n+2, n+3 and n+4 then
n+n+1+n+2+n+3+n+4 = 5n+10 = 35
n=25/5 = 5

Numbers are 5,6,7,8 & 9
5 & 7 are prime

IMO C

Second Approach: - 
If we assume numbers as n, n+1, n+2, n-1 and n-2 then
n+n+1+n+2+n-1+n-2 = 5n = 35
n=35/5 = 7

Numbers are 5,6,7,8 & 9
5 & 7 are prime

IMO C

But the end result of both approaches is the same.

It is better to assume 5 consecutive integers as n-2 ,n-1, n, n+1, n+2 since it eases the calculations in most cases.

Archit3110 · Answer

given
5x+10=35
x=5
so series ; 5,6,7,8,9
2 prime
IMO C

gracie · Answer

mean=35/5=7
sequence= 5 ,6, 7 ,8,9
 2 
C

TheNightKing · Answer

5+6+7+8+9 is 35. 2 numbers are prime in this.
IMO C.

ScottTargetTestPrep · Answer

The sum of 5, 6, 7, 8, and 9 is 35. Of these five numbers, 5 and 7 are prime numbers.

Answer: C

bumpbot · Answer

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The sum of five consecutive integers is 35. How many of the five conse

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The sum of five consecutive integers is 35. How many of the five conse

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