2 - Your closet has 10 pairs of white socks and 10 pairs of black socks. Suppose you are in the dark and need to pick one sock at a time, without knowing which. How many socks do you need to pick to guarantee you have a matching pair?
13 - In the book 'The Three Musketeers' by Alexandre Dumas, two of the musketeers are called Athos and Porthos. What was the name of the third musketeer?
14 - One boy can eat 100 chocolate bars in half a minute. Another boy can eat half of that amount in twice the time. How many chocolate bars can both boys eat together in 15 seconds?
15 - Potatoes are made up of 99% water and only 1% 'potato material.' João bought 100 kg of potatoes and left them in the backyard under the sun. When he returned, he noticed they had dehydrated and now had only 98% water. What was the new weight of the potatoes? Answer with numbers only, without 'kg'. Example: '10' means 10 kg.
16 - A farmer went to the bank manager to request a loan to buy animals. The manager made a deal: he would lend R$100, and the farmer would not have to pay back if he bought exactly 100 heads (animals) with the R$100. The only rule was that the farmer had to buy at least one of each type: cows, pigs, and sheep. Each cow costs R$10, each pig costs R$3, and each sheep costs R$0.50. How many animals of each type did the farmer buy? Separate answers with commas. Example: 'X, Y, Z' (X cows, Y pigs, Z sheep)
18 - Renato said that Naomy was the winner, with Milena in second place. Matheus said that Phoebe won, with Naomy in second. Actually, neither of them told the whole truth about the science fair results. Each made one true and one false statement about the ranking. What is the real ranking of the competitors? Use the names for first, second, and third place respectively. Example: Phoebe, Milena, Naomy
19 - You own a pet store and have canaries to organize in cages. If you put 1 canary per cage, there will be one canary left outside, meaning not enough cages. If you put 2 canaries per cage, there will be one cage left empty. How many canaries and cages do you have? Separate answers with commas. Example: 'X, Y' (X canaries, Y cages)
20 - Five competitors (A, B, C, D, and E) are competing in a swimming race that awards gold, silver, and bronze for 1st, 2nd, and 3rd places. The following conclusions about the race are false, but one statement from each could be true: A did not win gold and B did not win silver; D did not win silver and B did not win bronze; C won a medal, while D did not; A won a medal, while C did not; D won a medal and E also won one. Answer using letters for 1st, 2nd, and 3rd places respectively. Example: X, Y, Z
21 - A whale is 15 meters long. Its head is the same size as its tail. If the head were twice its real size, the head and tail together would be the same length as the rest of the whale's body. What are the lengths of the head, tail, and the rest of the body? Separate answers with commas. Example: 'X, Y, Z' (X meters for head, Y meters for tail, Z meters for rest of the body)
22 - Brent, Corrigan, and Bieber went birdwatching. Each saw a bird that none of the others saw. Each pair among them saw a bird the third did not. Finally, there was a bird all three saw. Of the birds Brent saw, 2 were yellow. Of those Corrigan saw, 3 were yellow. Bieber saw 1 yellow bird. Brent and Corrigan both saw 1 yellow bird together; Brent and Bieber saw 2 yellow birds together; Corrigan and Bieber saw 1 yellow bird together. How many yellow birds did each one see? Separate answers with commas. Example: X, Y, Z