Grade - examples - page 188

  1. Four numbers
    equilateral_triangle_5 The first number is 50% second, the second number is 40% third, the third number is 20% of the fourth. The sum is 396. What are the numbers?
  2. Prism diagonal
    hranol222_2 The body diagonal of a regular square prism has an angle of 60 degrees with the base, the edge length is 10 cm. What is the volume of the prism?
  3. Fractions
    zlomky_13 Three-quarters of an unknown number are 4/5. What is 5/6 of this unknown number?
  4. Regular prism
    hranol4sreg_9 The regular four-sided prism has a base of 25 cm2 and a surface of 210 cm2. Find its volume.
  5. Vertices of a right triangle
    right_triangle_5 Show that the points D(2,1), E(4,0), F(5,7) are vertices of a right triangle.
  6. The Stolen Money
    magic2_1 A man walks into a store and steals a $100 bill. 5 minutes later, he returns to the store and buys stuff worth $70. He pays with the bill that he had stolen, so the owner of the store returns him $30. How many dollars did the store owner lose?
  7. Discount sale
    penize_49 After the discount, the computer costs 9600, - CZK. How much did it cost when the price was reduced: a) by half b) by a third c) by one fifth and then by 160 CZK
  8. Cross road
    cyclist_34 From the junction of two streets that are perpendicular to each other, two cyclists (each on another street) walked out. One ran 18 km/h and the second 24 km/h. How are they away from a) 6 minutes, b) 15 minutes?
  9. Quadratic equation
    kvadrat_2 Find the roots of the quadratic equation: 3x2-4x + (-4) = 0.
  10. Inlet minus outlet
    inlets_6 Water flows into the tank through two pipes and flows out of the third pipe spontaneously. The pipe A itself would fill the tank in 3 hours, the pipe B itself would fille in 4 hours, and the pipe C itself would flow out in 12 hours. How long will the tank.
  11. Combine / add term
    combine Combine like terms 4c+c-7c
  12. A pizza
    pizza_11 A pizza place offers 14 different toppings. How many different three topping pizzas can you order?
  13. Variability
    lienky In the table bellow the number of wrong produced goods in two shifts: morning shift: 2; 0; 6; 10; 2; 2; 4; 2; 5; 2; afternoon shift: 4; 4; 0; 2; 10; 2; 6; 2; 3; 10; Compare the variability in both shifts, compare the average number of wrong goods on both
  14. Mushrooms
    hriby Fresh mushrooms contain 88% water, dried 14% water. How many kilograms of fresh mushrooms should be collected to get 3 kg of dried?
  15. Slant height
    cone_10 The slant height of cone is 5cm and the radius of its base is 3cm, find the volume of the cone
  16. Body diagonal
    cube_diagonals_2 Calculate the cube volume, whose body diagonal size is 75 dm. Draw a picture and highlight the body diagonal.
  17. Rhombus 29
    rhombus3_2 One of the diagonals of a rhombus is equal to a side of the rhombus. Find the angles of the rhombus.
  18. Sum of squares
    pytagorean The sum of squares above the sides of the rectangular triangle is 900 cm2. Calculate content of square over the triangle's hypotenuse.
  19. Fruits
    jablka_15 Amy bought a basket of fruits 1/5 of them were apples,1/4 were oranges, and the rest were 33 bananas. How many fruits did she buy in all?
  20. The King
    gold_4 The King wants to divide his sons equally. He has 42 rubies and 45 diamonds. How many sons and how will they share them?

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