Photo: noisiestpassenger via Flickr

Yesterday, we showed you 17 ridiculous job interview questions people have been asked in the past few months. They ranged from brain teasers:”There are 25 horses and 5 race tracks. How many races need to be run to select the top 5 horses?”

To insulting:

“What would you say if I told you that you aren’t ambitious?”

If you were stumped by any of them, here are the best answers people gave on Glassdoor’s Interview section.

### Having an infinite supply of water and two containers, one for 3 litres and one for 5 litres, how would you measure 4 litres?

- Fill and pour 3 litres into the 5 liter container
- Refill 3 liter container, transfer as much as possible to the 5 liter container
- Retain the one liter left in the 3 liter container, empty the 5 liter container
- Transfer the one liter from the 3 liter to the 5 liter container
- Refill the 3 liter and transfer it to the one liter in the 5 liter container...
- Fill

### You are on a game show. There are three doors. Behind one of them is a prize; the other two have coal. The host knows which door holds the prize. You choose door #1. Before it is opened, the host opens door #3 and reveals a lump of coal. You have the choice to stick with the door you chose originally or switch to door #2. What do you do?

When you chose door #1, there was a 66% chance that the prize was not behind that door. When the host revealed the coal, there was still a 66% chance the prize was not behind the door you chose.

Thus, you have double the odds of getting the prize by switching to door #2. The key to this puzzle is that the host knew which door has the prize.

### Three friends with different salaries need to find out their average salary without revealing individual salaries to each other. How?

Weigh balls 1,2, and 3 versus balls 4,5, and 6 first. This will result in three possible outcomes:

Case1:

If the weight of balls 1,2, and 3 = the weight of balls 4,5, and 6, then weigh ball 7 against ball 8 for your second measurement.

Case2:

If the weight of balls 1, 2, and 3 is greater than balls 4,5, and six, then weigh ball 1 against ball two for the second measurement. If ball 1 is the same weight as ball two, then ball 3 is the heaviest.

Case 3:

If balls 1, 2, and 3 weigh less than 4, 5, and 6, they weigh ball 4 against ball 5 for the second measurement. If ball 4 weighs the same as ball five, then ball 6 is the heaviest.

No matter which of the three scenarios happens, you still only need two measurements to find the heaviest ball.

A commenter who had previously been a brick layer answered:

'I learned that each brick is at least slightly different, and the placement of a brick is essential to the overall performance of the wall. Here are some brick laying tips to consider when formulating a response to this question:

- The first brick laid at the corner of a wall determines the position of every other brick in that wall.

- One brick laid with too large of a head joint, or not being level or plumb can effect rows of brick beside and above it.

- A soldier course of brick provides visual interest to an otherwise monotonous wall.

- Bricks are made of natural clay fired in a kiln; close up each brick has a slightly different design , texture, shape, and colour patterns, though all have almost exactly the same basic dimensions, though these can also vary.

- The keystone, or last brick placed in an arch helps support all the weight above the arch (which equally distributes that weight to the ground). Every brick in the arch shares the load equally.'

First race all 25 horses in groups of 5 to figure out the top 3 in each group (which will leave 15 horses). Call them:

A1 B1 C1 D1 E1

A2 B2 C2 D2 E2

A3 B3 C3 D3 E3

Here, A1 is faster than A2. A2 is faster than A3. The same applies for the rest of the groups.

Now race A1, B1 C1 D1 E1

Lets say the order of the horses according to ranking was A1, B1,C1,D1,E1

So A1 is No 1.

Now A1 is faster than B1 and B1 is faster than C1. So we can get rid of the entire D and E groups.

9 horse remain.

Also, A1 is faster than B1 and B1 is faster than C1. So we can get rid of C2 and C3. Now 7 horses remain.

A1 is faster than B1. B1 is faster than B2. Get rid of B3, and 6 horses remain.

Out of these, we know A1 is the fastest. So now race A2, A3, B1,B2,C1 to figure out No 2 and No 3 positions.

### If two cars are travelling in a two lap race on a track of any length, one going 60 mph and the other going 30 mph, how fast will the slower car have to go to finish at the same time?

The question decoded: It's a creative way of asking how you've solved a work problem that required you to think outside the box, or come up with a not-obvious solution.

If you've ever worked for a startup or had to establish a new role at your company, the possible answers are endless.

This type of problem is known as a 'Fermi' problem.

Say there are 120 million houses, they get painted every 10 years, and one person paints 40 houses per year (remember interiors take less time).

So 12,000,000 houses get painted every year / 40 houses = roughly 300,000 US house painters

There is really no right answer, but a safe answer is a dog.

Why?

They are loyal and do not bite unless they are backed into a corner.

The wrong answer would be a 'Cheat-ah.'

Start both timers together.

When the 4-minute timer is done, flip it. The 7-minute timer will have 3 minutes left.

When the 7-minute timer is done, the 4-minute timer will have 1 minute left.

Now you can count to 9 minutes by leaving the 4 minute to expire (1 min), flip it, and let it expire (4 min), flip it again and let it expire (4 min).

1 + 4 + 4 = 9

- As a door stop (keep the door open)

- As a weight object over a stack of papers or to keep a number of standing books up

- To kick it to pieces in a Karate show

- To slide behind the wheel of a big vehicle to keep them from moving when lifting heavy objects

- To ventilate a window or rest an AC unit on

- To study history (as in exploring different types of brick and brick making)

- As a unit of measure

The answer is 1/12 because there are two ways of rolling 11, rolling a 5 and a 6 or rolling a 6 and a 5 (for probability purposes there are indeed two different results).

There is only one way to roll more than 11 (two 6's). That means that out of 36 possible combinations, 3 qualify as being equal to or greater than 11, which means that the probability is 3/36, which reduces to 1/12.

- As part of a Christmas in July celebration.
- In ice cream
- Sell eggnog on sale over the summer as inventory to be delivered in the winter.
- Add rum and an umbrella and sell it as a cocktail.
- With Mickey Mouse

### Given a fleet of 50 trucks, each with a full fuel tank and a range of 100 miles, how far can you deliver a payload? You can transfer the payload from truck to truck, and you can transfer fuel from truck to truck. Extend your answer for n trucks.

### You are in a room with 3 switches which correspond to 3 bulbs in another room and you don't know which switch corresponds to which bulb. You can only enter the room with the bulbs once. You can NOT use any external equipment (power supplies, resistors, etc.). How do you find out which bulb corresponds to which switch?

- Turn on 2 switches.
- Turn one switch off after a few minutes.
- Enter room with bulbs.
- The bulb that is on is the only switch that is on.
- The bulb that is off but hot, is the switch that has been turned off.
- The bulb that is off and cold is the third switch.

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