Solution:

You are second in position. When you overtook the second positioned person, you actually took his place and thus you are positioned second now.

Solution:

This is because the queue for buying a donut is extremely long due to which the car engine becomes cool and gives trouble. While the queue for buying brownie is pretty small and thus the car gives no trouble at all.

Solution:

Britney speaks truth on only Thursday.

Solution:

Yes it is possible in Roman Numerals. In Roman Numerals,
9 = IX
10 = X
11 = XI

Thus by removing one from 9, you are getting 10 and by removing one from 11, you are getting 10 again.

Solution:

The number is 37.

The missing guess can be either 24 or 50 and the missing difference is 8.

Solution:

38

Explanation:
The total number of triangles are 8.

Let us divide the triangles in three categories: small, medium and large.

If we start with the small triangles, you can count a total of 24 triangles. 12 triangles (3 + 4 + 3 + 2) are upward facing and 12 are downward facing.

Next, we count the medium sized triangles. You can find a total of 12 triangles. 6 triangles (3 + 2 + 1) are facing upwards and 6 are facing downwards.

Lastly, if you calculate the large triangles, they are only two. One is upward facing and one is facing downward.

24 + 12 + 2 = 38.

Solution:

Because most of the buildings are not that tall enough.

Solution:

Reduction

Solution:

Yes. All three of them are the best. Laughter is the best medicine, living well is the best revenge and a good offense is the best defense.

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.

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:

72(18*4)

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:

Scent, Cent and Sent.

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:

Turning 30

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:

This puzzle is quite similar to the cheating husbands puzzle. The same logic applies here.

After the announcement, if there is only one person with green eyes, he will observe everyone and will come to the conclusion that he himself has green eyes.

If two persons have green eyes, they will see everyone and find out that there is one person with green eyes. So they will expect him to leave. But if no one leaves on that day, on the next day both of them will understand that they both have green eyes and will leave the island.

Thus if you keep going like this or apply the rules of induction, you will find that since there are 100 green eyed people on that island, all of them will leave the island on the 100th day after the announcement.

Solution:

Kungfu Panda

Solution:

60%

Explanation:
In all such cases where you have to find out the probability of anything with an already given situation, you have to use the formula for conditional probability.

In this case, you have to find out the probability that the second test was passed by a student given that he passed the first test already.

Therefore, P(Second/First) = P (First and Second)/ P (First)
= 0.25/0.42
=0.60
=60 %