the sum of four consecutive multiples of 16 is 2048 more than the second number. what is the third number????
plzz answer
problem on numbers
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seems eager to get ans, posted thrice
here we go
16x + 16x+16 + 16x+32 + 16x+48 - 16x+16 = 2048
48x + 80 = 2048
x =41,
third no 16*41 + 32 = 688
here we go
16x + 16x+16 + 16x+32 + 16x+48 - 16x+16 = 2048
48x + 80 = 2048
x =41,
third no 16*41 + 32 = 688
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Hi twinkzz,
If this were a GMAT question (and I don't believe that it is), then the question would come with 5 answer choices. These answers would make solving the question considerably easier because:
1) The correct answer MUST be a multiple of 16
2) By testing an answer, you could backtrack, figure out the 1st, 2nd and 4th numbers and prove whether they fit the facts of the question or not.
GMAT assassins aren't born, they're made,
Rich
If this were a GMAT question (and I don't believe that it is), then the question would come with 5 answer choices. These answers would make solving the question considerably easier because:
1) The correct answer MUST be a multiple of 16
2) By testing an answer, you could backtrack, figure out the 1st, 2nd and 4th numbers and prove whether they fit the facts of the question or not.
GMAT assassins aren't born, they're made,
Rich
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I agree with Rich - this seems way too computation-heavy for a GMAT problem. Vipugoyal's solution is correct, but it's important to understand how we got there.
If we have 4 consecutive multiples of 16, then the first term is going to be 16 times some number, the second term will be 16 times the next biggest number, and so on.
16x + 16(x + 1) + 16(x + 2) + 16(x + 3)
We're told that the sum of these terms is equal to 2048 more than the second number (a real GMAT question would use "term" instead of "number"). Since the second term was 16(x + 1), we can say:
16x + 16(x + 1) + 16(x + 2) + 16(x + 3) = 2048 + 16(x + 1)
Subtract that 16(x + 1) from both sides, and simplify.
Now at this point, you'll have to do way more math than you'd ever do on a real GMAT problem to solve. I'd disregard this question... and other questions from whatever source it came from.
Just make sure you understand consecutive integer setup!
If we have 4 consecutive multiples of 16, then the first term is going to be 16 times some number, the second term will be 16 times the next biggest number, and so on.
16x + 16(x + 1) + 16(x + 2) + 16(x + 3)
We're told that the sum of these terms is equal to 2048 more than the second number (a real GMAT question would use "term" instead of "number"). Since the second term was 16(x + 1), we can say:
16x + 16(x + 1) + 16(x + 2) + 16(x + 3) = 2048 + 16(x + 1)
Subtract that 16(x + 1) from both sides, and simplify.
Now at this point, you'll have to do way more math than you'd ever do on a real GMAT problem to solve. I'd disregard this question... and other questions from whatever source it came from.
Just make sure you understand consecutive integer setup!
Ceilidh Erickson
EdM in Mind, Brain, and Education
Harvard Graduate School of Education
EdM in Mind, Brain, and Education
Harvard Graduate School of Education