3rd and 4th grade, January, 2018

    A.1169. One Sunday afternoon, a family went on a tour boat ride around the island of Manhattan starting at 42nd Street. Susan observed that although many people were already on the boat, at the 23rd Street station 4 German and 3 Danish men, and 5 Canadian couples got on board. At the next stop, at 14th Street, 7 men and 8 women got off, and a group of 18 Japanese people got on. Next, at Christopher Street, a group of 25 children with 2 chaperons got on board, and two families of 5 people each got off the boat. At Battery Park half of all the passengers got off, and interestingly, nobody else got on. This way the boat arrived to its last stop with 66 passengers. With how many passengers did the boat leave from 42nd Street?

    A.1170. You can fill up a baby pool with thirty 5-liter buckets of water. Adam is always in a rush, so he spills a third of every full bucket on his way from the water faucet to the pool. How many trips does it take for him to fill up the pool?

    A.1171. Last summer, Adam and his friends entered the sailing competition with 5 solo boats. There were a total of 432 sailboats in the race. They did very well because all 5 boats finished in the top 10. Leslie’s and George’s boats finished after Zoe’s. Adam’s boat was faster than Mario’s but slower than Zoe’s. Leslie did beat Adam, and George finished behind Mario. What was the relative order of the 5 friends?

    A.1172. There are many animals hiding in the high grass on the side of a lake. One day Susan saw a few wild ducks, turtles and water snakes with a total of 16 heads and 28 legs. How many ducks, turtles and water snakes could she possibly have seen?

    A.1173. Fiona collects $10-, $20-, and $50-bills in her savings box because she loves to buy unique dolls for her collection. Last time she paid $640 from her box using an equal number of these 3 kinds of bills. How many $50-bills did she have in her box before paying if she had 5 of them left after she paid?

    A.1174. Olga keeps her 96 dolls in 4 boxes. One day, she put half of the dolls from the first box into the second box, 3 dolls from the third box into the fourth box, and this way she had an equal number of dolls in each box. How many dolls did she have originally in each box?

    A.1175. In a toy store, they sell two kinds of toy bears: one that can cry, and one that cannot. There are half as many crying bears as silent bears. The total number of bears is just as many more than 240 as is the number of crying bears less than 240. How many crying bears and how many silent bears are there in the store?

    A.1176. Tamara bought an 8-piece puzzle in a 10×10 square box, and now she wants to put then back into the box. Can you help her?

    Top view of the pieces:

     

    Top view of the box: 

    Please send your solutions here.

    The Sharma Kamala Educational Trust is sponsoring the participation of students from India. So, if you are a student living in India, please, send your solutions to: Group A from India

    Back to Paul Erdős International Math Challenge

    Back to 2017-18 Problems

    Current Standings in 2017-2018

    Posted in Uncategorized | Comments Off on 3rd and 4th grade, January, 2018