3rd and 4th Grade, March, 2022

    A.1409. On their trip around the world Fred and Ben saw a beautiful paper dragon in China. The body of the dragon with its head is 740 cm long. Its body is 460 cm longer than its head. How long …
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    5th and 6th Grade, March, 2022

    B.1409. I have four analog clocks. One of them is 2 minutes fast every hour, another one is 3 minutes late every hour, the third one is always on time, and the fourth clock does not work. One day in …
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    7th and 8th Grade, March, 2022

    C.1409. There are 5 identical circular disks placed on the table as shown below. With a straight line, divide in half the total area of the 5 disks. C.1410. Grandma bought 2 candles. The red is 1 cm longer than …
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    7th and 8th Grade, February, 2022

    C.1401. Two pieces of land are separated by the lines ABCD, as shown on the diagram below. AB=30 m, BC=24 m, and CD=10 m. AB, CD, and BC are parallel to the sides of the rectangle. We want to have …
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    5th and 6th Grade, February, 2022

    B.1401. One day 12 children from a class went to see a movie. On another day 9 children from the same class went to see a puppet show. 10 children from the class did not go to either program. At …
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    3rd and 4th Grade, February, 2022

    A.1401. There are a lot of geese on the market for sale. The sum of their heads and legs is 99. How many geese are there? A.1402. A cowboy has to count his cows. To make the job more interesting …
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    7th and 8th Grade, January, 2022

    C.1393. Find all those 2-digit numbers that are divisible by both the sum and the product of their digits. C.1394. We put down 10 identical coins on a circular line so that any two neighboring coins touch each other. 2 …
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    5th and 6th Grade, January, 2022

    B.1393. 2/3 of a group of people are sitting on 3/4 of the chairs in the room. At least how many people are there in the group? B.1394. Six people are estimating how many balls there are in a box. …
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    3rd and 4th Grade, January, 2022

    A.1393. The 8-eyed diver spiders love to feed on one-eyed winky lobsters. A few of the diver spiders are sneaking up on a group of winky lobsters right now. The 15 animals have a total of 36 eyes. How many …
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    7th and 8th Grade, December, 2021

    C.1385. Find all those 3-digit numbers in which every digit is a prime number and the number itself is divisible by these primes. C.1386. How many such number-pairs are there for which the greatest common factor is 7 and the …
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