Problem Solving

x, y, and z are consecutive integers, and x < y < z. What is the average of x, y, and z?

(1) x = 11

(2) The average of y and z is 12.5.

qa is D and this is a straightforward easier questions.

However, the question says consecutive and not explaining what kind of consecutive numbers.. Could it be argued that 1 is insufficient because x = 11 y=21 and z = 31? but the solution says the x being 11 forces y to be 12 and z as 13.. what is the correct rational here?

think of consecutive integers as "counting numbers." so if you are counting and you know the first number is 11 (since its the smallest number) then you just count up from there. consecutive numbers are 1,2,3,4,5 ect. (remember 0 is not considered a consecutive number)

wreelp wrote:think of consecutive integers as "counting numbers." so if you are counting and you know the first number is 11 (since its the smallest number) then you just count up from there. consecutive numbers are 1,2,3,4,5 ect. (remember 0 is not considered a consecutive number)

Great explanation until the "0 is not a consecutive number" part.

Here we know that we're dealling with consecutive INTEGERS. So, any series of integers counts... negative, 0, positive.. doesn't matter.

All of the following would be sets of 5 consecutive integers:

{1, 2, 3, 4, 5}
{0, 1, 2, 3, 4}
{-2, -1, 0, 1, 2}
{-58, -57, -56, -55, -54}

now i get it ,,, awesome thank you

just to make sure a consecutive set of numbers cannot count in the manner of 10, 20, 30, 40 but instead in a counting fashion as you explained earlier. correct me if i am wrong... thanks

Consecutive integers are integers that follow each other in order. They have a difference of "1" between every two number.

so you are right 10,20,30 are not consecutive integers

Odd consecutive integers are odd integers that follow each other. They have a difference of "2" between every two number.
Ex: 1.,3,5,7


Even consecutive integers are even integers that follow each other. They have a difference of "2" between every two number.
Ex: 2,4,6,8

So look out in the question what exactly is mentioned:
consecutive,odd consecutive or even consecutive