In the OG12, I am struggling to understand conceptually 2 questions related to number properties.
110) If p is the product of integers from 1 to 30 inclusive, what is the greatest integer k for which a factor of p?
A) 10
B) 12
C) 14
D) 16
E) 18
The book says answer C. It does so by counting the multiples if 3 between 1 and 30. I just don't understand the logic and reasoning behind it.
157) For any positive integer n, the sum of the first n positive integers (n(n+1))/2. What is the sum of all even integers between 99 and 301?
A) 10,100
B) 20,200
C) 22,650
D) 40,200
E) 45150
The answer is E. But I'm just not grasping the books explanation.
In the quant og DS:
39) Can the positive integer p be expressed as the product of two integers, each of which is > 1?
1) 31<p<37
2) p is odd.
I think each statement alone is correct. Book says only statement 1 is sufficient. Why???
thanks so much!
Lastly, guys, what are us study schedules like? I jus started studying last week and I'd like to see how other people are studying. I bought the 8 manhattan guides, and I'm working through those. How are you guys studying?
110) If p is the product of integers from 1 to 30 inclusive, what is the greatest integer k for which a factor of p?
A) 10
B) 12
C) 14
D) 16
E) 18
The book says answer C. It does so by counting the multiples if 3 between 1 and 30. I just don't understand the logic and reasoning behind it.
157) For any positive integer n, the sum of the first n positive integers (n(n+1))/2. What is the sum of all even integers between 99 and 301?
A) 10,100
B) 20,200
C) 22,650
D) 40,200
E) 45150
The answer is E. But I'm just not grasping the books explanation.
In the quant og DS:
39) Can the positive integer p be expressed as the product of two integers, each of which is > 1?
1) 31<p<37
2) p is odd.
I think each statement alone is correct. Book says only statement 1 is sufficient. Why???
thanks so much!
Lastly, guys, what are us study schedules like? I jus started studying last week and I'd like to see how other people are studying. I bought the 8 manhattan guides, and I'm working through those. How are you guys studying?
