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Kabir Firaque

Puzzles Editor Kabir Firaque is the author of the weekly column Problematics. A journalist for three decades, he also writes about science and mathematics.

Articles by Kabir Firaque

Problematics | Shopping basket

Given the price of each item, how many matchboxes, bars of detergent soap and packets of milk must you buy for the total spending to be exactly ₹500?

Welcome to Problematics!(Shutterstock)
Published on Jul 15, 2024 12:35 PM IST

Problematics | The truth about lying

A group of people includes one or more who are truthful and one or more who always lie. From their statements, can you work out who is what?

Representational image.
Published on Jul 08, 2024 11:21 AM IST

The physics and psychology of stampedes

In many stampedes, possibly including the one in Hathras, deaths occur due to a phenomenon that researcher Dirk Helbing describes as the “black hole effect”

Shoes are pictured where a stampede killed 121 people during a sermon at Hathras in Uttar Pradesh on July 3 (AFP FILE)
Published on Jul 05, 2024 02:18 PM IST

Problematics | Walking with a dinosaur

A brachiosaurus and a human walk the entire circumference of the planet together. Their feet obviously travel the same distance, but what about their heads?

Relative sizes of various dinosaurs and a human. (Wikipedia Commons)
Published on Jul 01, 2024 09:00 AM IST

Problematics | The perfect capital M

A child writes the capital letter M with two verticals that are perfectly straight but of unequal length. At what point do the two slanting lines meet?

Representational image.
Published on Jun 24, 2024 11:32 AM IST

Problematics | Double or nothing

Your neighbour offers you ₹5 lakh daily while you repay him every day with 1p, 2p, 4p and so on. Should you accept the offer for a month?

Representational image.(Pixabay)
Published on Jun 17, 2024 11:13 AM IST

Problematics | To eat ice cream or not to...

Three colleagues dine together at a canteen, but not all of them order ice cream. Who does so, and who does not?

Representational image.
Updated on Jun 11, 2024 05:25 PM IST

Problematics | A boy and his kite

Here is a new version of an old puzzle from Bhaskara’s Lilavati, adapted for Problematics solvers, plus a word puzzle as a bonus

Puzzle 93
Published on Jun 03, 2024 07:46 AM IST

Problematics | The mathemagic of dice

Here’s a magic trick that involves rapid addition of numbers on a set of dice. Can you work out the short cut involved?

Royal Vale Heath’s Deciphering Dice is marketed in a woodcraft version by Creative Crafthouse, US. (Source: Creative Crafthouse)
Published on May 27, 2024 01:31 PM IST

Problematics | Who owns the badger?

Crack this one loosely modelled on the original Einstein puzzle: 4 persons of different nationalities in houses of different colours, each with a different pet

Welcome to Problematics!
Published on May 20, 2024 10:59 AM IST

Problematics | An accountant’s missing figures

You know the price of one item and a few extra digits, nothing more. Can you work out how many items were sold and the total collected from the sales?

Representational image.
Published on May 13, 2024 09:39 AM IST

Problematics | I hold the four aces

A card trick that is ideally played on an unsuspecting audience at a party. Can you work out how it works?

File image
Updated on May 07, 2024 03:14 PM IST

Problematics | The length of a cricket run

What distance does a batter need to run to complete one run before turning back for a second? Meet two batters who run at different speeds

Running between wickets
Published on Apr 29, 2024 09:29 AM IST

Problematics | Watch those hands

Here’s an old-school puzzle involving the hour and minute hands of a watch. How frequently do they overlap or stretch out diametrically in a straight line?

Welcome to Problematics! (Shutterstock)
Updated on Apr 22, 2024 06:43 PM IST

Problematics | The IPL equation

One batter saves the day for his team with a fighting innings. How much does he score, and how many runs does his teammate contribute to a key partnership?

Representational image.
Published on Apr 15, 2024 03:14 PM IST

Problematics | Five parties, five defections

Meet five politicians who switch parties ahead of the elections. Which member came from which party, and who went where?

Here’s an Einstein puzzle about members from different parties switching sides ahead of the elections. (Shutterstock)(Shutterstock)
Published on Apr 08, 2024 05:07 PM IST

Problematics | How to win at Scrabble

A couple plays Scrabble for money, doubling the stakes in each successive round. If the husband loses ₹501 in the end, which games has the wife won?

Representational image.
Published on Apr 01, 2024 07:25 AM IST

Some dogs are aggressive, but don’t blame it on breed alone

Earlier this month, the government banned the sale and breeding of 23 dog breeds, describing them as “ferocious”

The government of India has banned the sale and breeding of 23 dog breeds (Representative Photo)
Published on Mar 27, 2024 04:41 PM IST

Problematics | The colours of mathemagic

Meet a magician deducing which member of the audience has which packet of Holi colours in his pocket. What is the mathematics that makes the trick work?

Representational Image
Published on Mar 25, 2024 07:51 AM IST

Problematics | As the crow flies

Centuries ago, one dropped pebbles into a jar to be able to drink water. This week, another smart crow is looking for an optimum flight path

Representational Image.
Published on Mar 18, 2024 11:32 AM IST

Problematics | The long and the short of growing flowers

This week, an ancient puzzle in a new setting that involves two rectangular flowerbeds, followed by a flower sale

Representational Image
Published on Mar 11, 2024 06:46 AM IST

Reconstructing Indians’ evolutionary history

Most Indians trace their ancestry to three groups, and all of them carry genes from Neanderthals and Denisovans, a new study finds

A new study has now reconstructed part of the evolutionary history of Indians after examining 2,762 genomes representing diverse population groups (REUTERS FILE)
Updated on Mar 06, 2024 09:40 PM IST

Problematics | Walk, don’t run

A speed-and-distance puzzle set in a forest where wild animals may be lurking, plus a sitter about the numbers on the face of a clock.

Representational Image.
Published on Mar 04, 2024 12:09 PM IST

Scientists make key progress in developing antibody against most snake venoms

Scientists have developed an antibody that can neutralize toxins from a variety of snake species, but a universal antivenom is still a long way off.

Scientists have developed an antibody that can block the effects of toxins in the venoms from a wide variety of snakes. (AFP)
Updated on Feb 27, 2024 04:58 AM IST
By, New Delhi

Problematics | Five Oscar nominees, five viewers

Ahead of the Oscars, an Einstein puzzle involving 5 Best Picture nominees, followed by a probability puzzle

Representational Image.
Published on Feb 26, 2024 09:47 AM IST

This scientist has led the way in tapping into the quantum world for new tech

Aditi Sen De received the GD Birla Award for Scientific Excellence for her contribution to the field of quantum technologies. Simply put, here's what she does

Dr Aditi Sen De(Sheeraz Rizvi/HT Photo)
Updated on Feb 23, 2024 04:20 PM IST

Problematics | Reluctant recruits go to war

This week, a mathematical puzzle in which you work out the number of men and women who enlisted for battle, plus a set of cricket anagrams.

Welcome to Problematics!(Shutterstock)
Published on Feb 19, 2024 08:00 AM IST

Problematics | Who wins this race?

Five athletes in their lanes, each from a different country and dressed in her favourite colour. Who is wearing what, and who wins?

Welcome to Problematics!(Shutterstock)
Published on Feb 12, 2024 08:00 AM IST

Problematics | The fast and the furious

We give you three runners, the differences in their speeds and in the time they clocked. What is the length of the race, and how long did each runner clock?

Welcome to Problematics!(Shutterstock)
Updated on Feb 05, 2024 11:26 AM IST

Science or pseudo-science? A debate rekindled

Indian-American doctor Deepak Chopra presented his latest book, Quantum Body, proposing the idea of a "quantum body" distinct from our physical body. Chopra asserts that understanding the quantum body can revolutionize disease eradication. The theory of consciousness, which suggests consciousness arises from quantum activity in the brain's neurons, is distinct but related. While some scientists have dismissed Chopra's ideas, others have taken the theory of consciousness seriously. Recent experiments have shown indications of quantum phenomena in the brain, but the Orch OR theory that connects these phenomena to consciousness remains unproven.

Deepak Chopra (centre) presented AIIMS Delhi with a copy of his latest book Quantum Body earlier this month. (AIIMS)
Updated on Jan 30, 2024 06:08 AM IST
By, New Delhi
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