Solution:

The pills can run for an hour.

Explanation:
If you had ninety minutes in mind, then you are wrong. You took the first pill at the zero minute. Then you took the second pill after 30 minutes and the third pill after 30 + 30 i.e. 60 minutes or an hour.

Solution:

This puzzle has no answer if you are considering this figure in a 2d domain. However if you follow it on a three-dimensional plane, you can do it like shown in the figure given.

Solution:

101/125

Explanation:
This is an extremely tricky question. You have to find the probability where all of them have same number in mind. But if you try to do that, you will have to do a lot of calculations and utilize your brain plenty much. However, the trick to do this question is something opposite. We are not implying that you won’t get answer by directly calculating the probabilities, but it will take much time.

However, if you just go on calculating the negative probabilities, then you can simply subtract it from 1 to find the positive probability. Let us begin the operations and not confuse you further more.

Let us take two friends in the beginning. The probability that Adam and Bella don’t have the same number in their respective mind will be 4/5.

Now let us include Christopher in the scene. The probability that Christopher don’t have a digit same as either Adam or Bella will be 3/5.

Let us now include Drew as well. The probability that she does not have any number in mind which is same as either Adam or Bella or Christopher will be 2/5.

Now the combined probability that none of them has the same number in mind will be:
4/5 * 3/5 * 2/5 = 24/125

Now the probability that they have same number in mind will be:
1 – 24/125 = 101/125

Solution:

CITIZENSHIP

Solution:

1653

Explanation:
For an ideal case, the batsman will hit a six on each ball. But if he hits six on the last ball of the over, the strike will change in the next over. Thus, the best he can do in the last ball is run 3 runs so that he retains the strike even in the next over. Thus the total runs that he can score in each over:
6 * 5 + 3 = 33
But this will have to go like it only till the 49th over. In the last over, he can hit a six in the last ball as well as that will be the last ball of the match.
Thus runs for the last over will be 6 * 6 = 36.
Hence the maximum runs = 33 * 49 + 36 = 1653

Solution:

If you analyze the numbers and arrange them alphabetically, you will find that the number 8 (eight) will be the first one to occur and number 2202 (two thousand two hundred and two) will be the last one.

Solution:

50%

Explanation:
The probability will be 50% only as it always was. The next flip of coin is not dependent on what the results were in the previous flips.

Solution:

L8

Explanation:
To know why, just read the number series upside down and you will find that the numbers are 91, 90, 89, 88, __, 86
So L8 when read upside down reads as 87.

Solution:

It is best if the person sits on the back of the train. After the stop, the train will be accelerating as it goes into the tunnel. Thus the train will be much master when the back of the train enters the tunnel. In this way, he will have to spend much less time in the tunnel.

Solution:

40

Explanation
The number 40 (Forty) is the only number in one million numbers whose letters are arranged in the order they are arranged in English alphabets as well.