Examples for 9th grade

  1. Christmas holidays
    christmas How many percent take Christmas holidays lasting 18 days from a school year that lasts 303 days? Round the result to two decimal places
  2. An equilateral
    rs_triangle2 An equilateral triangle is inscribed in a square of side 1 unit long so that it has one common vertex with the square. What is the area of the inscribed triangle?
  3. Sweets, candy
    bonbons Grandfather gave out sweets to four children. At the last moment, two more children came, so in order to have them all the same, each of the four children would receive four candies less than they would have received if they had not. How much did my grand
  4. Hectares of forest
    stromy 12 workers plant 24 ha of forest in 6 days. In how many days will 15 people and 12 people plant the same area?
  5. Height of the cuboid
    diagonal_rectangular_prism Cuboid with a rectangular base, measuring 3 cm and 4 cm diagonal has a body 13 centimeters long. What is the height of the cuboid?
  6. Pears and oranges
    hrusky There are 3 times as many pears as oranges. If a group of children receives 5 oranges each, there will be no oranges left over. If the same group of children receives 8 pears each, there will be 21 pears leftover. How many children and oranges are there?
  7. The regular
    ihlan_rez The regular quadrilateral pyramid has a volume of 24 dm3 and a height of 45 cm. Calculate its surface.
  8. Medians in RT
    right_triangle The rectangular triangle ABC has a length of 10 cm and 24 cm. Points P, Q, R are the centers of the sides of this triangle. The perimeter of the PQR triangle is:
  9. Triangular prism - regular
    prism3s The regular triangular prism is 7 cm high. Its base is an equilateral triangle whose height is 3 cm. Calculate the surface and volume of this prism.
  10. Permille of alcohol
    heart I have 2 per mille of alcohol in my blood. How many milliliters is it when I have 5 liters of blood?
  11. In the classroom
    skola_1 There are 30 boys and a few girls in the class. In the six months, 28 boys and all girls benefited, which was 95% of all pupils. How many pupils are there in the classroom?
  12. Hemisphere cut
    odsek_gule Calculate the volume of the spherical layer that remains from the hemisphere after the 3 cm section is cut. The height of the hemisphere is 10 cm.
  13. Kostka
    sphere_in_cube Kostka je vepsána do koule o poloměru r = 6 cm. Kolik procent tvoří objem kostky z objemu koule?
  14. Horses playground
    kone_dzokej The fence for the horses has the shape of a rectangular trapezoid with an area of 400 m2, the base lengths should be 31 m and 19 m. How many meters of boards will they need to fence it if the boards are stacked in 5 rows?
  15. Corona again
    flu If the population on long island is 7.75 million and the coronavirus has affected 22,178. What percent of the population is affected. (looking for 1 in? If possible)
  16. Compute 4
    14-12-12 Compute the exact value of the area of the triangle with sides 14 mi, 12 mi, and 12 mi long.
  17. Sum of the seventeen numbers
    seq_sum The sum of the 17 different natural numbers is 154. Determine the sum of the two largest ones.
  18. Triangular prism
    hranol3b The base of the perpendicular triangular prism is a rectangular triangle with a hypotenuse of 10 cm and one leg of 8 cm. The prism height is 75% of the perimeter of the base. Calculate the volume and surface of the prism.
  19. Right angle
    triangles_1 If a, b and c are two sides of a triangle ABC, a right angle in A, find the value on each missing side. If b=10, c=6
  20. Penalty daily
    bank_1 John was to pay CZK 1,500. If he does not pay on time, he will be charged a penalty of 0.5 per mille of the amount owed for each day of delay. He will remember in 30 days. How much is the penalty?

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