Gmat Prep (Product of least and greatest)

IMO D.

How did u arrive to your answer.?

The answer is indeed D.

6 consecutive integers, n = lowest integer * greatest integer

Statement I

the greatest number is 20
the smallest number = 20-6 +1 = 15
n= 15*20

sufficient.


Statement II

The mean is 17.5

In an evenly spaced set MEAN = MEDIAN
The integers above the median = 18,19,20
The integers below the median = 15,16,17
n=15*20

Sufficient.

Hence D is the answer.

Thanks...Pretty nice explanations....I GOT IT....

parallel_chase wrote:The answer is indeed D.

6 consecutive integers, n = lowest integer * greatest integer

Statement I

the greatest number is 20
the smallest number = 20-6 +1 = 15
n= 15*20

sufficient.


Statement II

The mean is 17.5

In an evenly spaced set MEAN = MEDIAN
The integers above the median = 18,19,20
The integers below the median = 15,16,17
n=15*20

Sufficient.

Hence D is the answer.

hey Parallel chase..
how you come up with the smallest number = 20-6 +1 = 15 ??

dferm wrote:If n is the product of the least and the greatest of 6 consecutive integers, what is the value of n?

(1) The greatest of the 6 consecutive integers is 20.
(2) The average(arithmetic mean) of the 6 consecutive integers is 17.5.

Can someone help me on this question....

First number : k
Last number : k+5

St1)

k+5 = 20

k = 15 SUF

St2)

k+....k+5/6 = 17.5

k = 15 SUF

Stmt I

If the greatest number is given then we can get to the lowest then to n

SUFF

Stmt II

Avg is 17.5 Sum=105

Since they are consecutive integers only one unique set of 6 consecutive integers will give a sum of 105. Even if one number changes the sum will be different

Hence we can find the smallest and greates then n from here

Hope I dint miss something here.

D)

cramya wrote:Stmt I

If the greatest number is given then we can get to the lowest then to n

SUFF

Stmt II

Avg is 17.5 Sum=105

Since they are consecutive integers only one unique set of 6 consecutive integers will give a sum of 105. Even if one number changes the sum will be different

Hence we can find the smallest and greates then n from here

Hope I dint miss something here.

D)

GOOD NEWS CRAMYA!! YOU DID NOT MISS ANYTHING BRO!! YAY

Funny..

Let the numbers be a, a+1, a+2, a+3, a+4, a+5.

given a(a+5) = n ; what is n?

stmt 1:
a+5 = 20
so a = 15.
From this, we can get all the numbers of the sequence. Any property can be
ascertained.
Sufficient.


stmt2)
avg of the 6 numbers is 17.5.
ie (a+ a+5)/2 = 17.5 (coz avg of sequence of n consecutive # = (1st# + last#)/2

= 2a +5 = 17.5.
So a can be calculated.
Sufficient.

D

Good Explanations guys..

I have one more question..

In consecutive integers, why don't we consider the question as an even/odd consecutive integers also ??

In consecutive integers, why don't we consider the question as an even/odd consecutive integers also ??

Among any 2 or more consecutive integers it will have atleast one even and one odd(may be more of each also depends on the number of consecutive intgers and whether u start wioth even or odd as the first in the list).


Consecutive even integers or Consecutive odd intgers are not the same as consectuive intgers and hence we dont bring that in to the picture


P.S (fyi)

In general

consecutive integers: x, x+1, x+2 ....... or k, k+1,k+2... whatever variable u pick

consecutive odd or consecutive even integers can both be represented as

x,x+2,x+4......

Eg: x=1 it will 1,3,5 - consecutive odd
x=2 it will be 2,4,6 - consecutive even

Hope this helps!

Regards,
CR

Thanks Cramya

No problem!

Also keep in mind that 0 is even

(and)

Odd and even intgers can be negative also.

-3,-1,1,3 are also consectuive odd intgers

-2,0,2,4 are also consecutive even integers

dferm wrote:If n is the product of the least and the greatest of 6 consecutive integers, what is the value of n?

(1) The greatest of the 6 consecutive integers is 20.
(2) The average(arithmetic mean) of the 6 consecutive integers is 17.5.

Can someone help me on this question....

I guess this is where being simple minded helps but I took this approach.

(1) Highest number =20 so : 20 ; 19 ; 18 ; 17 ; 16 ; 15

since I knew I could find all six integers, I knew I could find the sum of the least and the greatest. I guess I missed that the consecutive integers could be even but I didn't think about that because I figured they would specify.

(2) The average of the 6 consecutive integers is 17.5 so I wrote down 17.5 and circled it and then wrote 17 to the left of it, 18 to the right of it, 16 to left of 17 and 19 to right of 18, and so on. This gave me a 15-20. So i figured I would be able to solve the equation by just having this option.

So that is how I chose D.

Was that luck that I came up with that answer? Should I be considering the even numbers as integers or even other patterns?