of x, y, and z

[sanju09]

Are the integers x, y, and z consecutive?

1. The arithmetic mean (average) of x, y, and z is y.
2. y - x = z - y.

[spoiler]Source: majortests.com[/spoiler]

[clock60]

got E here
(1) (x+y+z)/3=y from here x+z=2y. and many versions are possible
y=1, x=1,z=1 not consecutive
y=2,x=1,z=3 consecutive
insufficient
(2)y-x=z-y, 2y=x+z the reasoning the same as for st 1
both insuffiicent

[selango]

1. The arithmetic mean (average) of x, y, and z is y.
2. y - x = z - y.


Stmt1,

x y z

Median=y

y=(x+y+z)/3

If the numbers are consecutive,mean of numbers is equal to median.

Sufficient.

Stmt2,

y - x = z - y.

2y=x+z

y=(x+z)/2

If the numbers are consecutive, median is equal to average of range.

Sufficient.

Hence D

[sanju09]

1. The arithmetic mean (average) of x, y, and z is y.
2. y - x = z - y.


Stmt1,

x y z

Median=y

y=(x+y+z)/3

If the numbers are consecutive,mean of numbers is equal to median.

Sufficient.

Stmt2,

y - x = z - y.

2y=x+z

y=(x+z)/2

If the numbers are consecutive, median is equal to average of range.

Sufficient.

Hence D

This is mere misinterpretation of the correct definitions of few mathematical terminologies.

[selango]

oops..my mistake..

Got it..its works also for evenly spaced numbers.rt?

[outreach]

1. The arithmetic mean (average) of x, y, and z is y.

(x+y+z)/3=y
x+z=2y

x z y
1 4 7 no corresponding num
3 4 5 corresponding num

insuff

2. y - x = z - y.
x+z=2y
x z y
1 4 7 no corresponding num
3 4 5 corresponding num

insuff


comb 1 and 2
insuff

Are the integers x, y, and z consecutive?

1. The arithmetic mean (average) of x, y, and z is y.
2. y - x = z - y.

[spoiler]Source: majortests.com[/spoiler]