New math problems - page 4

  1. Quadratic inequation
    eq2_8 If 5x + x² > 100, then x is not
  2. Cube in sphere
    sphere4 The sphere is inscribed cube with edge 8 cm. Find the radius of the sphere.
  3. Electricity consumption cost
    Temelin4veze1 Last year Karol family reduced its electricity consumption by 31% compared to the previous year and paid CZK 2883 less. How many CZK is electricity last year and how many two year ago?
  4. Trapezoid 15
    trapezoid3 Area of trapezoid is 266. What value is x if bases b1 is 2x-3, b2 is 2x+1 and height h is x+4
  5. Steamer
    parnik_3 At 6 hours 40 minutes steamer sailed from the port at speed 12 km/h. At exactly 10 hours started sail motorboat at speed 42 km/h. When motorboat will catch steamer?
  6. Real estate
    house Residential house has three entrances numbered by odd numbers arithmetic progression. The sum of the two numbers on the corner entrances is 50. Calculate the highest of this three numbers.
  7. Isosceles right triangle
    IsoscelesRightTriangle Contents of an isosceles right triangle is 18 dm2. Calculate the length of its base.
  8. Diagonals
    stvorec_7 Draw a square ABCD whose diagonals have a length of 6 cm
  9. Cubes
    krychlicky Carol with cut bar 12 cm x 12 cm x 135 cm to the cubes. Find the sum of all the surfaces of the resulting cubes.
  10. Concrete pedestal
    krychle_10 The carpenters made wooden mold on a concrete pedestal in the shape of a cube with edge 2 meter long. What is the area in which the concrete touches wooden molds? (No lid or bottom)
  11. Salami
    salama How many ways can we choose 5 pcs of salami, if we have 6 types of salami for 10 pieces and one type for 4 pieces?
  12. Trees
    jablone Along the road were planted 250 trees of two types. Cherry for 60 CZK apiece and apple 50 CZK apiece. The entire plantation cost 12,800 CZK. How many was cherries and apples?
  13. MO Z6-6-1
    kruhy_1 Write integers greater than 1 to the blanks in the following figure, so that each darker box was product of the numbers in the neighboring lighter boxes. What number is in the middle box?
  14. Pizza 4
    pizza_6 Marcus ate half pizza on monday night. He than ate one third of the remaining pizza on Tuesday. Which of the following expressions show how much pizza marcus ate in total?
  15. 3 children
    cukr_2 3 children had to divide 4 pounds is candy. How much candy did each child get?
  16. Benches
    garden_13 The park has 64 benches. Occupied are by 18 more than empty. How many benches are occupied and empty ?
  17. Isosceles triangle
    triangles_8 Calculate area and perimeter of an isosceles triangle ABC with base AB if a = 6 cm, c = 7 cm.
  18. Rhombus
    kosostvorec_6 If we increase the rhombus side by 2.4 cm; its perimeter is 20 cm. How long was the side of the rhombus?
  19. Workers
    okno2_1 Group of workers washing half of the windows of the building in two hours. How long will take half the workers wash all the windows of the building?
  20. Garden
    zahon_4 Rectangular garden 31 meters 40 centimeters long and 20m30cm wide adjacent with the shorter side with another (fenced) garden and on one longest side is 1 meter wide gate. How many meters of fence is needed to buy? (Estimate, calculate, verify a test ca

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