Sunday, November 7, 2010

Sunday, November 7, 2010

  • Consider three unit disks (i.e., of radius 1) touching each other. I am interested in finding the area of the triangular cavity between the three disks. Draw the triangle joining the center of the disks, and find the area of the part of the triangle, which is outside of the disks.
  • Consider a cube, which is painted red, and has side length of 4cms. This cube is divided into unit cubes (i.e., each of side 1cm). How many small cubes will have (a) exactly three sides painted red (b) exactly two sides painted red (c) exactly one side painted red (d) no sides painted red.  Repeat the same problem with the starting cube of side length 1cm, 2cm, 3cm, .. Whats the pattern?
  • Ad's friend decided to hangout on Friday evening in the Ottawa Expo. They planned carefully and decided that they needed to spend $96 for all the fun activities - and decided to contribute equally. But on the most exciting day, some of his friends (being very unreliable) didn't show up.! Now the remaining ones had to contribute $4 more than what they initially planned! How many of them were eventually at the expo?
  • Mr Every T. Wrong is expert in getting everything wrong! He was asked to multiply a number by 4 and then add  eight - and he landed up dividing by 4  and then subtracting 8. He got 1 as his answer! What should be the correct answer.
  • The overhead water tank on the Moodie drive supplies water to whole of Barrhaven.  It requires 4 hours to fill it completely and  6 hours to empty it. Usually the water tank is getting simultaneously filled as well as emptied. How long will it take to fill it? Suppose it takes x hours to fill and y hours to empty, what should be the relationship between x and y. This is a typical producer-consumer problem! Assuming that x is less than y, then how many hours it will take to fill the tank completely in terms of x and y?
  • Ad is taller than Rd by 25%. Then, by what percentage Rd is shorter than Ad?
  • The height of parliament hill in Ottawa is 92 mts and the height of the National Art Gallery  is 60 mts. They are approximately 200 mts apart. Assuming that their base is at the same level,  what is the distance between their tops? 
  • You have a bag consisting of 10 red and 10 blue marbles. What is the smallest number of marbles you need to draw to be sure that you have exactly three of the same color? What happens when you have 10 red and 15 blue? What happens when you have three colors - say consisting of 10 red, 10 blue and 10 green - and you want to draw three of the same color?
  • Whats the right length of laces that you need for your ice skates?  You need about 20  cms  to be left after tightening your skates to tie them up. There are 10 eyelets on each side,  3cms apart, and the distance between  two consecutive eyelets on the same side is about 1 cms.

No comments:

Post a Comment