Smita04 wrote:
[x] denotes to be the least integer no less than x. Is [2d] = 0?
(1) [d] = 0
(2) [3d] = 0
I did not jump into the equations, but tried to solve logically. Please let me know if wrong.
We need to find out if [2d] = 0?
Again its a YES or NO, question, getting Either in the statements will help us to the solutions.
(1) [d] = 0
Now according to the question [x] = integer no less than x
Hence, considering two extremes for evaluating this particular case, Lets take
[0.12] = 0 as well as [0.99] = 0 (both are valid for [d] =0)
therefore, [2d], i.e. taking the same values as above
[0.24] = 0, but [1.98] = 1
so we cant say most definitely that [2d] =0
Not Sufficient.
(2) [3d] = 0
again considering etremes here,
lets take
Minimum value => 3d = 0.12 (you can take less then this as well, i am just taking this for easy divisibility purpose, as anything less then 0.12 will also result in 0 we already know that)
and
Maximum value => 3d = 0.99
[3d] = 0 holds for both the values.
now, [2d]
minimum= [0.8] =0
maximum= [0.22] =0
hence, no matter what range we take for 3d, 2d will always be less then that.
Thus, if [3d]= 0, holds true, then [2d] =0 should hold true as well.
Hence, B