For positive integer values of n, the operation n# is defined as the

Question

For positive integer values of n, the operation n# is defined as the sum of all integers from 1 to n, inclusive. For example, 4# = 1 + 2 + 3 + 4 = 10. If 15# – 14# = k#, what is the value of k#?

A. 1
B. 4
C. 5
D. 14
E. 15

Kudos for a correct  solution .

ManojReddy · Answer

15# – 14# = k#
15 + 14# - 14# = k#
15 = k#

Ans:E

dhawalbp · Answer

If you are asking K# then it is : 15#-14#= 15 ---> E
Else if you are asking K, then it is K=5---->C

ENGRTOMBA2018 · Answer

The question is asking about k# and not k

KS15 · Answer

15#=1+2+3+4.....+15=120
14#=1+2+#+4....+14=105

15#-14#=15
Now, 15=k#
Answer E

ashokk138 · Answer

Sum of first n numbers is = n(n+1)/2
here,
K# = 15# - 14#
K# = (15*16)/2 - (14*15)/2

Solving K# = 15(8-7) = 15. Option E.

Bunuel · Answer

800score Official Solution:

The symbol # is a function. These types of functions are common on the GMAT. Using the definition of n#, we know that:
15# – 14# = (1 + 2 +…+ 15) – (1 + 2 +…+ 14) = 15.

So k# must equal 15, or  choice (E) .

Raome · Answer

k=15
15= 1 + 2 + 3 + 4 + 5
Therefore, shouldn't #k=#5.

Am I missing something?

Bunuel · Answer

We are asked to find the value of k#, not k itself.

For positive integer values of n, the operation n# is defined as the

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For positive integer values of n, the operation n# is defined as the

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