Interview Question

IT Role Interview

-Portsmouth, England

IBM

How many man hours would it take to clean every single window in London?

AnswerAdd Tags

Interview Answers

21 Answers

24

Thank you for the time, this job's not for me...

Alan on

11

If that includes Windows Vista it doesn't seem worthwhile.

Moss on

11

Based on London's population and an average time per window you could give a rough estimate. Each person has a home and a workplace (schools or other public institutions are also here). So I have 2 windows for me at home and 2 at home, maybe more.. Then I take all cars of London probably the same or more as the population have about 6 windows each So the formula would be: time_per_window * ( population * ( 2 at home + 2 at work + 6 per car))

Ovidiu on

12

5 minutes in Total. Everybody should clean their own window same time

Kunhayamu on

4

Window cleaner can give this answer; I've no experience of such kind.

Window cleaner can give this answer; I've no experience of such kind. on

4

It depends on the project goal and how you're going to define success. How big is the team? Are they experienced with the work and equipment (high-rise window cleaning will be involved). This could easily become an endless task as windows become dirty again, without a clear objective to say "this is the end" how do you know when you're complete?

Anonymous on

3

It depends. How many single windows are there in London? Inside and outside? What's the average and mode window size? Do you want a range or an estimate based on the average window size?

Poot on

2

Twice half the time.

mike on

1

It depends how many windows are married and also how rough the neighbourhood is. Are you sure this for IBM and not Everest?

Anonymous on

1

Next time there is a cause for a1 minute silence, ask everyone to spend that minute to clean one window in London. So total will be 1 minute.

Anonymous on

1

How many people in my team?

Anonymous on

0

Lets just estimate how many windows there are in London,Y, and then work out how long it takes to clean one window,X. Crudely speaking your answer is Y times X. Of course some windows are larger than others and some windows are less accessible than others so these variables would have to be worked into the equation. and by the way I don't work on Sundays, and when I die I suggest you arrange somebody to take over from me.

Anonymous on

0

It depends what time of the day it is. I was on holiday at one hotel and we were warned about the window cleaner doing the windows at 2 am in the morning!

Anonymous on

0

The Windows would be all self cleaning

Kim on

0

This depends on method of cleansing. Are we talking traditional spray and sponge, high pressure hose pipes or large scale pouring of water and soap over the whole of the city? Also "every single window", what is classed as a window as well as are we talking figuratively or literal?

Nat on

0

-Population of London say 10million -Say each home has 5 windows on average (larger houses will have more, flats will have less) -2.5 people per home So the houses of London have 10m*5/2.5 = 20m windows -Say 70% of London is at work -Estimate about a window at work per 10 employees So workplaces of London have 10m*0.7/10 = 700k Say 21m windows, a skilled cleaner could probably do 5 minutes per window, so roughly 102million minutes, or 1.7million man hours.

Chris on

0

First I need more data: 1. How many windows are in London - get data from a designated place (the office that permits construction) 2. Take into account that some of these windows won't be there anymore/yet (say 10% - but find better data about that probability) 3. Make an algorithm that sorts windows via sizes (homes vs. offices) and difficulty level (skyscrapers) 4. Run few iterations with different time spend for each window, and finally get the average. 5. Show data about home and office windows separately (as they vary by size and time spent) and show overall average. I'm not a magician, can't calculate it without data 🦸🏻‍♀️

Kamila on

0

How long have you got?

Anonymous on

0

1 window takes 10 min to be cleaned by 1 Cleaner then the result will be 0.167 Manhour

Islam Kassem on

5

10 minutes per 1 window

Ruslan on

0

0. Hire women for that.

Sergey on

Add Answers or Comments

To comment on this, Sign In or Sign Up.