Problem Solving Pack 3, Question 1 What is the positive difference...

Question

QUANT 4-PACK SERIES Problem Solving Pack 3 Question 1 What is the positive difference...

What is the positive difference between the sum of the squares of the first 4 positive integers and the sum of the prime numbers between the first square and fourth square?

A) 11
B) 12
C) 13
D) 14
E) 15

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This question is part of the Quant 4-Pack series

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chetan2u · Answer

hi,
cannot think of an immediate way other than calculations..
only POE could tell us the answer will be an odd number..
ans 11..
A

AkshdeepS · Answer

My Solution:

Square of first four positive integers = 1^2+2^2+3^2+4^2=30

Prime nos. between 1^2 & 4^2 or 1 and 16 are 2,3 5,7,11,13.

Their sum = 41

Positive difference = 41-30=11

Answer is A

MathRevolution · Answer

Forget conventional ways of solving math questions. In PS, IVY approach is the easiest and quickest way to find the answer.

What is the positive difference between the sum of the squares of the first 4 positive integers and the sum of the prime numbers between the first square and fourth square?

A) 11
B) 12
C) 13
D) 14
E) 15

the sum of the squares of the first 4 positive integers = 1^2 + 2^2 + 3^2 +4^2 = 30

the sum of the prime numbers between the first square(=1) and fourth square(=16) = 2+3+5+7+11+13=41.
So the difference between 41 and 30 is 11.

So the answer is (A).

EMPOWERgmatRichC · Answer

Hi All,

Certain Quant questions on Test Day are just about doing organized work and making sure that you're following the 'instructions' in the prompt.

Here, we're asked to compare two sums:
1) The sum of the squares of the first 4 positive integers
2) The sum of the prime numbers between the first square and fourth square

For the first sum, we need the SQUARES of the first four positive integers. That sum is....

1^{2}  +  2^{2}  +  3^{2} +  4^{2}  = 1 + 4 + 9 + 16 = 30

For the second sum, we need the PRIMES between 1 and 16. That sum is...

2 + 3 + 5 + 7 + 11 + 13 = 41

The positive difference between those sums is 41 - 30 = 11

Final Answer:  A

GMAT assassins aren't born, they're made,
Rich

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Problem Solving Pack 3, Question 1 What is the positive difference...

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GMAT Problem Solving (PS) Questions

Problem Solving Pack 3, Question 1 What is the positive difference...

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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