I was overwhelmed by the responses to my piece on maths question papers. Here?s the most interesting mail from a student who has survived a fresh assault from another education board (my barb was aimed at the West Bengal Board) : ?I perfectly agree with you. I am a CBSE class X student. Day before yesterday I sat for my maths exam. It was absolutely rubbish. There were two geometry questions in which I had to apply several odd tricks. I failed to do so and thus lost eight marks. I am very good in mathematics and science. I have qualified for the Astronomy Olympiad and have won many prizes and scholarships, including the second level of the National Talent Search Examination, but sadly, my 10th class mark won?t reflect my aptitude in maths. So, I wish the boards consider the plight of students like me who wish to make a career in science and maths.... Yours etc. Arnab.?

PUZZLE 1: An old farmer died and left 17 cows to his three sons. In his will, the farmer stated that his oldest son should get 1/2, his middle son should get 1/3, and his youngest son should get 1/9 of all the cows. The sons, who did not want to end up with half cows, sat for days, trying to figure out how many cows each of them should get. One day, their neighbour came by to see how they were doing after their father?s death. The three sons told him their problem. After thinking for a while, the neighbour said: ?I?ll be right back!? He went away, and when he came back, the three sons could divide the cows according to their father?s will, and in such a way that each of them got a whole number of cows. What was the neighbour?s solution?

PUZZLE 2: A boy leaves home in the morning to go to school. At the moment he leaves the house, he looks at the clock in the mirror. The clock has no number indication and for this reason the boy makes a mistake in interpreting the time (mirror-image). Assuming that the clock must be out of order, the boy cycles to school, where he arrives after 20 minutes. At that moment the clock at school shows a time that is two-and-a-half hours later than the time that the boy saw on the clock at home. At what time did he reach school?

Solutions on April 11

CORRECT ENTRIES

March 14

Vinay Pagaria, Lake Town; Major Sanjay Bhatia; Partha Datta,Jadavpur; Rajat Tibrewal,Calcutta Boys'; Sudipta Roy, Suri; Arka Majumdar, IIT-Kgp;Vinay Agarwalla, Cal-20; Arnab Dey, Kolaghat;Ayan Sammader Chaudhuri, B. Garden; A. K. Majumdar, Cal- 106; Divya Kaul,BIT Mesra; Vanika Modi Ranchi; Debasis Ganguly,Alumnus Software; Santanu Tosh, East Garo Hills; Shayoni Chakraborty, IISWBM; Dipanjan Biswas,IIT-Kgp; Robert Hsu; Arka Kundu, IIT-Kgp; Soumyajit Roy, IIT-Kgp; Sreechandra Banerjee, Cal-19; Benjamin Slade, Shillong; Trishul Chakraborty, Joynagar; Sourav Sengupta, ETCE-Jadavpur;Mahamudur Islam,Midnapore; Arkajyoti Roy Chowdhury, Calcutta Boy's; Rima Das, Narula Instt;Sabyasachi Chakrabarty,La Marts; Debjani Sinha, Cal- 63; Somnath Barik, Durgapur-4; Priyanka Majumdar, Cal-19; Shayak Bhattacharjee,Patha Bhavan; Sandeep Jain, Dimapur; Vaarnan Drolia, Cal-19

PUZZLE CRACKED

Solution for puzzles on March 14: Because it was given that exactly six statements were true, suspect B must be the offender.

Hint: There are two pairs of contradicting statements in which nothing is said about the possible offender: A1-C1 and C3-D2. These statements always result in two true and two false statements. In addition, it follows from the introduction that statement A3 is true. So, we have a total of three true and two false statements. On the basis of an assumption about which suspect is the offender, we can count how many of the remaining statements are true. Statement: A is the offender: B is the offender: C is the offender: D is the offender: None of the suspects is the offender:

The total count: Four true, three false; three true, four false; four true, three false; four true, three false; four true, three false.