The "length of the integer" refers to the number of prime factors, not necessarily distinct, that x has(If x=60, the length of x would be 4 because 60=2*2*3*5). what is the greatest possible length of integer z if z<1080?
A.13
B.10
C. 9
D. 7
E. 6
How to solve this PS. anyone pls help
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- gmatboost
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That answer is correct. To expand a bit on the reasoning:
Your goal is to get the maximum length subject to the constraint z < 1080. To do this, use the smallest possible prime number (2) to build up the length. Multiply 2 by itself until the product is as close to 1080 as possible without going over. Since 2^10 = 1024, 10 is correct.
Your goal is to get the maximum length subject to the constraint z < 1080. To do this, use the smallest possible prime number (2) to build up the length. Multiply 2 by itself until the product is as close to 1080 as possible without going over. Since 2^10 = 1024, 10 is correct.
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- shashank.ism
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Here we see that we have to find the greatest possible length if the integer z. So to increase the number we should first try to use smallest number possible prime number.srini1988 wrote:The "length of the integer" refers to the number of prime factors, not necessarily distinct, that x has(If x=60, the length of x would be 4 because 60=2*2*3*5). what is the greatest possible length of integer z if z<1080?
A.13
B.10
C. 9
D. 7
E. 6
so lets start with (2)^10 = 1024 < 1080.
If we try any other combination like 3, 5 in it we will get smaller length.
Hence Correct Ans is B
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