Cornell physicist Veit Elser has been engrossed in resolving a pivotal question in biological imaging, says Science Daily. In discovering an algorithm critical for X-ray diffraction microscopy, Elser and colleagues solved two problems. First, they gave researchers a new tool for imaging the tiniest and most delicate of biological specimens. And second, they discovered that the same algorithm also solves the internationally popular numbers puzzle Sudoku. They used difference-map algorithm that tackles problems for which the solution must meet two independent constraints. In the case of Sudoku, the constraints are simple: Each of nine numbers, considered alone, appears nine times in the grid so that there is only one per row and column. And all nine numbers appear within each of the nine blocks.

PUZZLE 1: A 120 wire cable has been laid firmly underground between two telephone exchanges located 10km apart. Unfortunately after the cable was laid it was discovered to be the wrong type, the problem is the individual wires are not labelled. There is no visual way of knowing which wire is which and thus connections at either end is not immediately possible. You are a trainee technician and your boss has asked you to identify and label the wires at both ends without ripping it all up. You have no transport and only a battery and light bulb to test continuity. You do have tape and pen for labelling the wires. What is the shortest distance in kilometres you will need to walk to correctly identify and label each wire?

Solutions on March 27

CORRECT ENTRIES

February 27

Madhab Dutta, Kapragali; Ritika Ray; Priyangi Das; Chanchal Kumar Roychowdhury; Soumya Mondal; Amalesh Paul; Sanjeeb Roy; Ruchi Agarwal; Soumya Bit; Sangram Ray; Devang Shah; Aditya Anurag; Mufidul Islam Khan; Namrata Palit; Sayan Chatterjee; Max Steel; Subham Soni; Navajyoti Paul; Ayan Chanda; Sreechandra Banerjee; Nirmal Kumar Agarwala; Aveek Ghosh; Harsh Baid; Ranjit Singh; Soumyajyoti Saha; Mohit Prasad; Roshni Roy; Sahidul Islam, Farraka; Tuhin S Mondal; Shantanu Das; Satwinder Singh, Durgapur; Shreya Chauhan; Arnab Thokder, Sudipto Basu; Sudip Roy; Tuhin Subhra Dey, Subhasis Ray; Mahendra Pal; Shantanu Saha; Paroma Datta; Anindita Das; Sarwan Kumar Khaitan; Priyam Chakravarty; Zia ul Hoque; Anwesha Chowdhury; Debraj Datta; Mukti Chakrabarti; Roshni Basu Majumdar; Suvajeet Dey; Ashwini Damani; Apratim Kaviraj; Ruturaj; Jagannath Das; Arindam Chakraborty; A. K. Majumdar; Kapil Nandwana; Aneesh Sharma; Pratik Sharda; A.C.R.Lakshman; Pankaj Kumar Bhar; Krishti Chakraborty; Gargi Roy; Atul Goyal; Ananya Saha; Somava Chakrabarti; Kumardip Sen; Henna Sethi; Megha Lundia, Madhyamgram; Parthasarathy Basu, Ahmedabad; Kumardip Sen; Sulakshana Ghosh Bhunia; Ravi Raja; Harjesh Bawa; Arnab Kr Sadhukhan.

PUZZLE CRACKED

The response this week (February 27) was great. Ravi Raja was methodical in his approach. Here goes his solution:

Solution 1: There were 3,000 gold coins, 4,000 silver and 5,000 bronze. Hint: Let us suppose that Dimwit was speaking the truth. Then we see that both the

statements of Beefbrain becomes true and vice versa. Which is a contradiction. Hence Thickplank was speaking the truth.

Solution 2: Grandma was 72 years old. Hint: Let the two digits be x and y. Then 10x+y-10y-x=45 so 9(x-y)=45. This gives x-y=5. The possible values of x and y are (9, 4), (8, 3), (7, 2) and (6,1). But there is only one case where both the digits are prime and that is (x, y) = (7, 2). Hence grandma’s age is 72 and dad’s age is 27.