# #24. Quick brainteaser games for consulting/ tech job interviews

Try to quick­ly ESTIMATE the answers to the ques­tions below, based on your own log­i­cal approach. The goal is not to find out (or Google) the right answer, but to, first, iden­tify a log­i­cal approach that can help “guessti­mate” an appro­pri­ate range–say + or – 30% of the actu­al answer– and then com­plete the cal­cu­la­tions (ide­ally men­tally, but you can also take notes) to pro­vide a good-enough estimate.

Ques­tions:

1) How many times heav­ier than a mouse is an elephant?.

2) How many fire­fight­ers are there in San Francisco?.

3) How many trees are there in NYC’s Cen­tral Park?.

The Answer appear below. Again, the key here is to try, plan the steps towards the solu­tion, and do the men­tal cal­cu­la­tions to find a rea­son­able range. That’s the brain chal­lenge. The goal is not to find the pre­cise cor­rect answer.

1) Around 150,000. An aver­age ele­phant weighs 4,000 kg; an aver­age mouse 25 grams.

2) Around 350 fire­fight­ers on duty on any giv­en day, out of a pool of 1700 fire­fight­ing over­all staff.

3) There are over 26,000 trees (of approx­i­mate­ly 175 species) in the Park.

Next brain teas­er in Sharp­Brains’ top 25 series:

Posted in

1. Tim on September 19, 2006 at 1:28

maybe

1) 10,000 times (1 ton ver­sus 100 grams)

2) 800 fire­fight­ers (80 sta­tions x 10 in each)

3) 5,000 trees

2. tiki on September 19, 2006 at 11:58

1. 8000

2. 650

3. 1500

3. Alvaro on September 22, 2006 at 6:14

Again, the key here is to try, plan the steps towards the solu­tion, and do the men­tal calculations.That’s the brain exercise.

1. Around 150,000. Ele­phant: 4,000 kg on aver­age; mouse is 25 grams.

2. Around 350 fire­fight­ers on duty on any giv­en day, out of a pool of 1700 fire­fight­ing and emer­gency med­ical field personnel

3. “There are over 26,000 trees of approx­i­mate­ly 175 species in the Park.” More infor­ma­tion at http://www.centralparknyc.org/17613/4604933

4. Mitch on January 6, 2008 at 3:33

I said 80000 times as heav­ier (ele­phant 2000kg, mouse 25g).

Im aus­tralian so i have no idea about those amer­i­can-based questions.

5. Aaron on March 23, 2008 at 10:51

1. 14,000 times heavier

2. 1,300

3. 3,624

6. Bushy Mouse on August 23, 2008 at 12:20

1 mil­lion
30.000
200.000

7. datasam on August 28, 2008 at 4:47

my no-calc guessti­ma­tions were:
10,000
5,000
8,000

SHARPBRAINS is an independent think-tank and consulting firm providing services at the frontier of applied neuroscience, health, leadership and innovation.
SHARPBRAINS es un think-tank y consultoría independiente proporcionando servicios para la neurociencia aplicada, salud, liderazgo e innovación.