Practice Questions Chat

Thank Bunuel. However, the solution is not clear to me. It would be great if you could explain. Thanks in advance.

My take on the above question:
For determining the denominator:
100 is to be divided in three non-zero positive variables and as it is positive, minimum value of all three is 1. Therefore, 97 is to be divided amongst three variables now. Place two separator between 97 identical elements and total therefore, total elements are now 99. Position of these seprator can be arranged in 99C2 ways.
For numerator we will have to use the condition x>20, y>10 and z>20. Therefore, taking their minimums as 21, 11 and 21 (totalling to 53), we are left with 47 to distribute among theee variables as earlier. This will give 49C2. So probability will be 49C2/99C2. @chetan2u @bunuel can verify if this makes sense or not

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A similar question for basic understanding

treat this problem as a distribution of 100 chocolates between 3 students such that each will have atleast 1 chocolates

We are to find the minimum sum of the blued boxes right?

and for x> 20, y>10 and z>20 give them already 21,11, 21 respectively then problem will change into x + y + z = 47

15 ?

35 wanted A but in the end has 20 so 15 didn’t ended up in team A

I think you maybe unable to reach to the solution because the table created by you is wrong. Horizontically it should be A, Not A and vertically it should be B, Not B. Try this you will reach to the solution. The solution for the same is discussed here : of-the-50-researchers-in-a-workgroup-40-percent-will-be-137538.html Hope it helps!

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i marked option b

can someone post its soln

Someone help me with this question.

Have you tried drawing the problem statement ? Drawing three circles with collinear centers while marking center-center distances might help.

Actually I know the answer with normal difference method. But was trying in different way to reduce the time. But I was wrong

is the answer 1.493 x 10^11??

yes sorry my mistake

If approximation works as pwr answer choice, you can take common factor as 3.84 and make 14.96 approximately 4 times of 3.84

I find this method a little difficult, this is how I did it: 1.496 x10^11 is actually 1496 x 10^8 and distance till moon is also given in 10^8 terms. please correct me if I’m wrong

I haven’t tried it on paper so far. You may be coreect if you have solved it already

explain plz

no its 12

first for topmost 9 squares if you view from top view the squares which forms plus sign so out of those 5 remove center piece you will get 4 pieces will have 2 face black. Then the 2 vertical corner cubes of each side of first two layers, total we have 4 sides, So, 4*2 = 8 such cubes Therefore total of 8+4 = 12 cubes