Examples for 8th grade - page 28

  1. Metal alloy
    ocel What is the ratio of metals in the alloy that is in the 50 tonnes of steel to 30 kg nickel?
  2. Rectangular trapezoid
    rt_licho The rectangular trapezoid ABCD is: /AB/ = /BC/ = /AC/. The length of the median is 6 cm. Calculate the circumference and area of a trapezoid.
  3. Subway
    metro Subway train went between two stations that gradually accelerated for 26 seconds and reached a speed of 72 km/h. At this rate, went 56 seconds. Then 16 seconds slowed to a stop. What was the distance between the stations?
  4. Trapezoid ABCD v2
    trapezium_table Trapezoid ABCD has length of bases in ratio 3:10. The area of riangle ACD is 825 dm2. What is the area of trapezoid ABCD?
  5. Car inflation
    car_1 About what percentage price of car increased if price rose from €1880 to €2200?
  6. Three digits number
    plot How many are three-digit integers such that in they no digit repeats?
  7. Hurry - rush
    bus_3 At an average speed 7 km/h I will come from the school to the bus stop for 30 minutes. How fast I need to go if I need to get to the bus stop in 21 minutes?
  8. Motor physics
    car_motor Car traveling at 130 km/h on the highway. Pulling power of the motor is 8 kN. Determine engine power in kW.
  9. Pure quadratic equation
    kvadrat Solve pure quadratic equation ?.
  10. Components
    components In the box are 8 white, 4 blue and 2 red components. What is the probability that we pull one white, one blue and one red component without returning?
  11. Temperature calculus
    snowman Calculate percentage of temperature decrease if changed from -5 °C to -16 °C?
  12. Diamond
    rhombus2_2 Determine the side of diamond if its content is S = 353 cm2 and one diagonal u2 = 45 cm.
  13. Liters in cylinder
    cylinder_1 Determine the height at which level 24 liters of water in a cylindrical container having a bottom diameter 36 cm.
  14. Triangle
    Triangle_trig Calculate the sides of the triangle if its area S = 630 and the second cathethus is shorter by 17.
  15. Sisters
    sisters Sisters Hanka and Vera goes mostly tograndmother by bicycle. Journey took Hanka 30 minutes and Vera 20 minutes. How long will Vera catch up with Hanka when started from home five minutes later than Hanka?
  16. Diameter
    diameter_circle If the endpoints of a diameter of a circle are A(10, -1) and B (3, 10), what is the radius of the circle?
  17. Money
    hyperinflation Everyone complains about the lack of money. In fact, there is no shortage of money, but the relative scarcity of goods and things that people buy for money. Calculate what percentage of the price of all goods and services rose immediately, if everyone has
  18. Angles ratio
    3angle_1 In a triangle ABC true relationship c is less than b and b is less than a. Internal angles of the triangle are in the ratio 5:4:9. The size of the internal angle beta is:
  19. Vacation
    motion Parents piggybacking children on vacation to its grandmother and grandfather at a city distant 150 kilometers. They agreed to meet halfway. Parents will be travel at 90 km/h, grandmother and grandfather at 60 km/h. Parents depart at 12:00 hours. When grand
  20. Cube - wall
    cubes_2 V kocke ABCDEFGH je ?. Aký je povrch kocky?

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