ABACUS International Math Challenge

for

3rd and 4th graders

January, 2002

 

A.289. It takes Mowgli 40 minutes to walk to the lake and come back on his elephant. When he rides his elephant in both directions, it takes him 32 minutes. How long would the trip take Mowgli if he walked both ways?

 

A.290. 14 little monkeys are playing on a meadow. Out of them there are 4 monkeys who have 3 siblings playing with them, there are 6 monkeys who have 2 siblings playing with them, there are 2 monkeys who have 1 sibling playing with them, and only 2 monkeys have no siblings on the meadow. The little monkeys were brought to the meadow by their mothers. How many monkey mothers are waiting for their little ones at the edge of the meadow?

 

A.291. Snakes, frogs and parrots are talking in the jungle. All together they have 8 heads and 14 legs. How many of each animal are there in the group?

 

A.292. The monkey king gave a party. His servants served 3 barrels of coconut cocktail, a total of 533 liters. After they served 75 liters from the first barrel, 46 liters from the second barrel, and 52 liters from the third barrel, all of the barrels had the same amount of cocktail left in them. How many liters of cocktail was in each of the barrels at the beginning of the party?

 

A.293. At the party, somebody took a piece from the king's cake before they served it. One of the suspects, Maky, said for his own defense: "Those, who deny that I did not eat the cake, are not telling the truth." Did Maky eat the cake if he is telling the truth?

 

A.294. Mowgli collected 3 different fruits into a bag, a total of 30 pieces. Without looking he has to take out 19 pieces to be sure that he took out an orange. He would have to take out 24 pieces in order to be sure that he has a coconut. How many pieces does he have to take out without looking to be sure that he took out at least one piece from every fruit?

 

A.295. There is a big lake in the middle of the jungle. The birds brought a beautiful waterlily and put it on the lake. This flower doubles in size every day, and so it covers the whole lake on the 8th day. What part of the lake was covered on the 6th day?

 

A.296. Mowgli is making a climbing net for the little monkeys from a long liana. First he cuts half of the liana and yet a half a meter, then he cuts the half of the rest of the liana and yet another half meter, and then he cuts the half of the rest of the liana and yet another half meter. He still has 8 meters of liana left. How long was the liana originally?

 

Please, send your solutions to:

diveki@gcschool.org

 

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