C.1465. 95% of a 10 kg watermelon is water. When you put it in the sun, it starts to dry out, so now only 90% of it is water. How many kg is the mass of the watermelon now? C.1466. We drew …

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# 5th and 6th Grade, March, 2023

B.1465. Sara has 3 red, 3 blue and 3 green pearls. She would like to arrange them on a 3×3 grid so that every row and every column has one of each color. She considers two arrangements to be different if …

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# 3rd and 4th Grade, March, 2023

A.1465. In the Animal Olympic Games there were 8 teams in Volleyball. Every team played every other team to decide which was the best team. How many games did the teams play all together? A.1466. In Weight lifting the elephant that finished …

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# 3rd and 4th Grade, February, 2023

A.1457. In a Kennel Club there are 85 dogs. Each of them is one of three colors- white, grey or multicolored. Actually, 7 of them are white, and 1/6 of the rest of the dogs are gray. How many multicolored dogs …

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# 5th and 6th Grade, February, 2023

B.1457. We bought 5 cheese danish and 4 strawberry danish and paid a total of $4.45. Next time we bought 8 cheese danish and 7 strawberry danish and paid a total of $7.45. How much would we have to pay if …

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# 7th and 8th Grade, February, 2023

C.1457. There are 32 students in a class. Everybody studies either French or Spanish. 9 students study both languages. Prove that a different number of students study French and Spanish. C.1458. Find the smallest positive whole number that when added to , you …

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# 3rd and 4th Grade, January, 2023

A.1449. There are many necklaces among the Pharaoh’s jewelry. 1/3 of the necklaces are made with emerald, and 1/4 of them (that is 24 necklaces) are made with zephyr. How many necklaces have emerald? A.1450. Write different positive whole numbers …

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# 5th and 6th Grade, January, 2023

B.1449. If you fold the following diagram along the lines, you can make a cube. At every vertex, calculate the product of the numbers on the sides running into that vertex. Which one of these products is the greatest? B.1450. …

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# 7th and 8th Grade, January, 2023

C.1449. In Math class the teacher wrote a number on the backboard. One student said: “This number is divisible by 31.” Another student said: “It is divisible by 30.” The next student said that it is divisible by 29, and …

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# 7th and 8th Grade, December, 2022

C.1441. How many different ways can you go from one vertex of a cube to the vertex that is farthest away, along the edges of the cube if you can visit each vertex no more than once? C.1442. The ABCD …

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