Regular readers of Problematics need no introduction to Einstein puzzles, nor the reason why they are also called zebra puzzles. The benchmark puzzle of this form involves different people who have different pets, one of which is a zebra. What cannot be established, of course, is whether it is true that Einstein himself had posed that puzzle to people he knew. Let that remain the legend that it has become.
I remember having invoked Einstein’s zebra in a previous puzzle of my own. I am bringing the zebra back this week, but this puzzle is slightly more intricate than the previous one. It involves six sets of variables (including the positions of houses) as compared to the four or five sets in many of my previous Einstein puzzles,
The new puzzle is not necessarily more difficult than my previous ones, but those extra variables will hopefully allow you to spend some extra time solving it, and thereby derive some extra fun out of it.
#Puzzle 124.1
A lane in a locality has a row of houses on either side. The houses on one side are #101 to #105; those on the other side of the lane are not relevant to our puzzle. The occupants of houses #101–#105 have ordered various items of fast food. These are delivered by the same agent, who goes serially, starting from house #101 at one end of the lane, delivering the order, and moving to the next house and then the next, completing his deliveries at house #105 at the far end of the lane.
Along the way, the delivery agent observes the different colours of the five house, and the names and occupations of the individuals living in them, all of whom happen to be single men. Most interestingly, the agent notes that each house has a different pet — including, of course, a zebra. Your clues below:
1. House #102 is white; house #103 is purple.
2. The occupant of house #104 orders fries.
3. The ostrich and her owner live in house #105.
4. The penguin and his owner live in house #103.
5. The gorilla and her owner live next door to the purple house.
6. The rhino is male, the zebra female.
7. The zebra owner’s house comes before the blue and orange houses.
8. The burgers are delivered before the zebra owner’s order.
9. The zebra owner receives his order after Vijay but before Vinoo.
10. Eknath’s house is at one end of the row, Vijay’s is at the other end.
11. Vinoo is a screenwriter, Mansoor has another occupation.
12. The filmmaker lives in the blue house, the poet in another house.
13. Eknath receives his order immediately after the sculptor.
14. The pizza is delivered immediately after Lala’s order.
15. The fries are delivered immediately before the sandwiches.
16. The man ordering pizza and the painter live in adjacent houses.
17. The order for tacos is not from the brown house.
There can be only one kind of question at the end of any Einstein puzzle. Who lives where and does what, what has each one ordered, and what is his pet? Please send your answers in tabular form.
#Puzzle 124.2
A store is getting rid of its old stock and offering socks at two prices: one kind at 3 pairs @ ₹100, another at 2 pairs @ ₹100. A woman sends her children there with ₹700, asking them to share it fairly. They spend the entire amount and distribute the purchases neatly, with each child getting the same number of pairs of either or both kinds.
How many children, how many pairs of socks, and what kind(s)?
MAILBOX: LAST WEEK’S SOLVERS
#Puzzle 123.1
Hi Kabir,
The minimum number of coins that must have been stolen from the museum is 200. The final shares of the thieve #1, #2, #3, #4 and #5 are, respectively 40, 1, 69, 51 and 39.
Taking the total number of coins as 5x, the stepwise division is shown in the tables. The final total comes to (405u + 325)/32. For this expression to be a whole number, the minimum value of u is 15. Substituting u = 15 in the above expressions lead to 200 as the total number of coins.
— Sabornee Jana, Mumbai
#Puzzle 123.2
Dear Kabir,
The minute hand is always at 90° from the 12 o'clock position at 15 minutes past any hour. The hour hand moves 30° in one hour, or 7.5° in 15 minutes. The angle between the two hands at 12:15 is 90 –7.5 = 82.5°, and thereafter keeps changing by 30° every hour. Considering only angles less than 180°, the angles from 12:15 to 11:15 are (in sequence): 82.5°, 52.5°, 22.5°, 7.5° (the hour hand has crossed the minute hand), 37.5°, 67.5°, 97.5°, 127.5°, 157.5°, 172.5° (360 – 187.5), 142.5° and 112.5°
— Yadvendra Somra, Sonipat
***
Hello Kabir,
A note on Puzzle #122.2 about the weight of coins. I appreciate the solution given. However, the apparatus at hand was a “balance” and not a “scale”. To my mind that’s the difference between being relative vs absolute.
— Sanjay Gupta, Delhi
Point taken: we use a balance to compare two unknown weights, and a scale to find absolute weights. The puzzle used a word that may have misdirected some solvers.
Solved both puzzles: Sabornee Jana (Mumbai), Yadvendra Somra (Sonipat), Sanjay Gupta (Delhi), Dr Sunita Gupta (Delhi), Professor Anshul Kumar (Delhi), Shishir Gupta (Indore), YK Munjal (Delhi)
Solved #Puzzle 123.1: Anil Khanna (Ghaziabad)
Solved #Puzzle 123.2: Ajay Ashok (Delhi)