If Y is a real number, is Y 10? (1) {Y} = 10, where {Y} denotes the

Question

If Y is a real number, is Y > 10?

(1) {Y} = 10, where {Y} denotes the least integer greater than or equal to Y.

(2) Y^2 is NOT equal to 100.

DavidTutorexamPAL · Answer

We'll translate our statements into equations to help us understand them.
This is a Precise approach,

(1) tells us that 9>Y>=10 . Therefore it is Y>10 is definitely false.
Sufficient.

(2) This is clearly not enough as Y can be almost any number.
Insufficient.

(A) is our answer.

ColumbiaEMBA · Answer

I would go with A.

{Y} tells us that 9<Y<10; hence, Y is definitely < 10 which makes this answer sufficient.

B is useless.

MrCleantek · Answer

1. It could be equal to 10 or greater -> Not helpful
2. Not much info except that Y is not 10 -> Not helpful

We need both to eliminate doubt in choice 1
Answer: C

saquib1192 · Answer

It’s C, we need the second statement to eliminate the possibility of y =10

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ColumbiaEMBA · Answer

The question asks whether Y is greater than 10. If Y is less than 10 or equal to 10, it still answers the question as No. hence, you do not need B and A is sufficient.

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ColumbiaEMBA · Answer

For 1) how are you arriving at that Y could be greater than 10? Think you may be misunderstanding the definition posted in the stem.

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MrCleantek · Answer

I am seriously not getting the statement 1 interpretation! Can anyone give details please

ColumbiaEMBA · Answer

If Y is a real number, is Y > 10?

(1) {Y} = 10, where {Y} denotes the least integer greater than or equal to Y.

1 basically says the following: {Something in here} = 10. {Something in here} means that whatever {Something in here} is equal to, it is the  LEAST integer greater than or equal to  Something in there  . In simple English: whatever is inside the curly braces, is the smallest integer that is either equal to or greater than the number it is representing. SO: {y} = 10 means 10 is the smallest integer greater than or equal to Y, which means Y can be 10 or less than 10. Said differently {9.1} would equal 10 because the smallest integer greater than or equal to 9.1 is 10.

Make sense?

amanvermagmat · Answer

We can also memorise something like this:

If {y} is the least integer greater than or equal to y , then:
 - If y is an integer, {y} will be equal to y
 - If y is not an integer but a decimal, then {y} will be equal to the  first integer to the right of y  on the number line
So, eg, if y=-3, then {y} = -3 but if y = -3.22, then {y} = -3. If y = 0.68, then {y} = 1. If y = -0.76, then {y} = 0.

On the other hand,  if   is the greatest integer less than or equal to x , then:
 - If x is an integer,   will be equal to x
 - If x is not an integer but a decimal, then   will be equal to the  first integer to the left of x  on the number line
So, eg, if x=3, then   = 3. If x=-4, then   = -4. If x=0, then   = 0. 
But if x=-3.22, then   = -4. If x=0.68, then   = 0. If x=-0.76, then   = -1.

push12345 · Answer

(1) {Y} = 10, where {Y} denotes the least integer greater than or equal to Y.

Two cases
1) Y=10 
II)9<Y<10

In both cases y is always less than 10 so sufficient

(2) Y^2 is NOT equal to 100

Y 2 can be greater than or less than 100
 So y can be greater than or less than 10

So Insufficient

A is answer

Give kudos if it helps

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If Y is a real number, is Y > 10? (1) {Y} = 10, where {Y} denotes the

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