Batch 2 - Class 58 - Mathematical Hockey

• (Arvind Gupta 19) Use eighteen of the dominoes from a standard double-six set to form a 6 x 6 square in such a way that the number of dots in each of the six rows and columns and the two main diagonals is the same. 

• Can you tile a 6x6 grid with 2x1 dominos, so that there are no fault lines (i.e. any horizontal or vertical line has at least one dominos going across it?)

  Answer: Can't be done - each of 10 lines in 6x6 grid divides the region into two even areas, so at least two dominoes must cross it. So there must be at least 20 dominoes, but there are only 18

• Two teams; each player must take turns - can do random or assigned play as long as everyone gets turn
• 5 minutes per problem. Person to answer first wins if answer is right. Else the other person wins without having to answer
• If no one answers for 5 minutes, then 30 seconds for the next person scheduled on the team to answer
• Draw the hockey rink and goal posts and zones
• Display problems on TV screen

1. MC Diaries - Chap 11 Exercise 1: Three humpties and 4 dumpties weigh as much as 5 humpties and 3 dumpties. Who is heavier, a humpty or a dumpty?
• Answer: dumpty
2. MC Diaries - Chap 11 Problem Set - 4: You have 7 coins and know that exactly one of them is counterfeit - lighter than the real ones. There is a balance scale. How many weighings are required to find out which one is counterfeit.
• Answer: 2. Weight three and three. And then one weighing within a group of 3
3. MC Diaries - Chap 11 Problem Set - 9*: The king gave a total of 3 gold and 3 silver coins to 3 knights, each knight getting two coins. The first knight knows his coins, but doesn't know what others have. Ask one question to the first knight, answerable in "Yes", "No" and "I dont know" to figure out what the first knight has?
• Answer: Many answers possible - one is "Does anyone apart from you have two gold coins"
4. MC Diaries - Chap 12 Problem 6: Yesterday on Halloween, Muskaan, Anisha, Kushaan and Aryan went trick or treating. Muskaan collected more candy than anyone in the group. Anisha's candy harvest was not the smallest. Kushaan collected more than Aryan. Did the girls or the boys collect more candy?
• Answer: Girls
5. MC Diaries - Chap 13 Exercise 2 and Problem 3: Which of the following shapes can be folded into a cube?
• (See presentation)
6. Dudeney 30: In throwing five pennies at the same time, what are the chances that at least four of the coins will turn up either all heads or all tails?

   Answer: 12/32
7. Dudeney 30: A man placed three one-rupee coins and two 50-paise coins in a bag. How much should be paid for permission to draw one coin from it? It is, of course, understood that you are as likely to draw any one of the four coins as another.

   Answer: 80 paise
8. MC Diaries - Chap 13 Problem 6: Snow White decided to make a quilt. She took a big square piece of fabric and cut it into 4 equal squares. While she was gone, the first dwarf came in, and cut a square into four smaller ones. Each of the other 6 dwarfs also did the same with a random square they picked up. How many pieces were there when Show White returned?
• 25 - Each person produced 3 additional pieces, and there was one original
9. UltimateBrainTrainer 79 - Look at the structure below and draw the shape from top, front and right view
1. 

   
   
10. Wash-Chudler: Show this image for one minute, and then switch it off. Now ask kids in each team, turn by turn, to recall and draw one item in the right place. Right answer moves the puck by one. Wrong answer moves it back by one.
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11. Personalities Quiz - Get people from both teams come forward, and draw a number from 1 to 14 - they have to identify that person
• (See presentation)