Solution:

5

Explanation
First three equation in the image can be written as :
a) 3 BED = 30
b) 2 BED + BUS = 40
c) BED + 2 BUS+ 2 TROPHY = 60

From equation a)
BED = 10

From equation b)
BUS = 40 -20 =20

From equation c)
10 + 40 + 2 TROPHY = 60

TROPHY = 5

Solution:

10

Explanation:
Equation 1 + 9 + 11 = 1 can be derived from
One (o) + nine (n) + eleven (e) = one => 1

Similarly for equation,
12 + 11 + 9
Twelve (t) + eleven (e) + nine (n) => ten (10)

Solution:

Yes, by adding 'G' to 'One'
G + One => Gone

Solution:

Your friend's statement is actually true and it's not different from what you have answered.

25 - 55 + (85 + 65) = 25 - 55 + 150 = 120 = 5!
5! (factorial) = 5 * 4 * 3 * 2 * 1 = 120

Yes, that was a tricky question, quite capable to confuse anybody.

Solution:

Both S and T are of same height because they are the same people.

Suppose that each person is marked with their respective number which also denotes their height.
Now when the longest from each row is called out, they will be 50, 100, 150 ... 500. Shortest among them will be 50 aka S.
When the shortest from each colum is called out, they will be 1, 2, 3, ....50. Longest among them will be 50 aka T.

Thus, they both are same person.

Solution:

60 minutes

Explanation:
Roy will be able to consume all the five tablets in an hour.

Tablet 1 will be taken in 0 min.
Tablet 2 will be taken in 15 min.
Tablet 3 will be taken in 30 min.
Tablet 4 will be taken in 45 min.
Tablet 5 will be taken in 60 min.

Solution:

Never

Explanation:
In the question, the distance of x miles is given at a particular moment. The middle car is running at that time at 50 MPH. The distance will keep increasing with time as three are running at different speeds. It will increase by x miles every hour till a certain point of time and then it will start decreasing till the fastest car meets the slowest again.

As per question, all the cars stop then. Thus, the distance will never be x miles again.

Solution:

If you remember the formulas, you will find out that the first option cannot exist.
Side A^2 + Side B^2 = Side C^2

Thus the only possible option here is the second one and of course, it will have a greater area then

Solution:

Since every bacterium divides into two in two minutes and we know the fact that the dish was half filled with bacteria at 3 pm, after exactly 2 minutes, all will divide into two and will fill the petri dish. Thus, the petri dish will become full at 3:02 pm.

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.