For any number X, {X} denotes the least non-negative number

Question

For any number X, {X} denotes the least non-negative number y such that X + Y is an integer. What is the value of 8.4 - {8.4}?

a) -0.4
b) 0
c) 0.6
d) 7.8
e) 8.0

blueseas · Accepted Answer

X + Y SHOULD BE NEAREST INTEGER.
8.4+Y = 9
Y= 0.6
THEREFORE
8.4 - {8.4}
 8.4-0.6= 7.8 
hence D

fozzzy · Answer

I think there is more to explain {x} regarding that symbol, there is a similar question ( not exactly similar but similar concept) in OG 13 #104 DS. I'm confused about that part.

mau5 · Answer

When you are confused about such questions, you can pick numbers to get a feel:

Take the entire description literally : {x} lets assume x = 7.9. Now as per the definition, {7.9} is nothing but the least non-negative number(y)(note, it can be zero too) for which, x+y would be an integer. Thus, it is easy to see that {7.9} = 0.1. It could have been 1.1 also, had the question not mentioned that it is "the least number".

Hope this helps. You can also post that question specifically (the one in OG) to clear your doubt.

blueseas · Answer

hi fozzy ,

just checked that qn from OG.

both have different definition for that symbol.

in this qn
 {X} denotes the least non-negative  number  y such that X + Y is an integer
here number can be integer and non integer,but it must be non negative.
example if X = 8.2 then Y = 0.8
if X = 9 THEN Y = 0

HOPE IT HELPS

ArunpriyanJ · Answer

Bunel,

I understood this Q after a bit of struggle. So i would like to practice questions of similar type. Could you kindly share the link for such Q's?

Thanks,
A

Bunuel · Answer

Check similar questions in  Rounding Functions Questions .

bumpbot · Answer

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For any number X, {X} denotes the least non-negative number

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For any number X, {X} denotes the least non-negative number

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