Examples for 8th grade - page 26

  1. Subway
    metro Subway train went between two stations that gradually accelerated for 20 seconds and reached a speed of 80 km/h. At this rate, went 41 seconds. Then 17 seconds slowed to a stop. What was the distance between the stations?
  2. Equilateral cylinder
    3d Equilateral cylinder (height = base diameter; h = 2r) has a volume of V = 221 cm3 . Calculate the surface area of the cylinder.
  3. Diamond
    rhombus2_2 Determine the side of diamond if its content is S = 500 cm2 and one diagonal u2 = 46 cm.
  4. Series
    posloupnost_an Andrew wrote this series of numbers: 1,3,7,15, .... n. Which number in the series does not belong? ?
  5. Trapezoid ABCD v2
    trapezium_table Trapezoid ABCD has length of bases in ratio 3:2. The area of riangle ACD is 956 dm2. What is the area of trapezoid ABCD?
  6. Motor physics
    car_motor Car traveling at 97 km/h on the highway. Pulling power of the motor is 6 kN. Determine engine power in kW.
  7. Triangle
    Triangle_trig Calculate the sides of the triangle if its area S = 630 and the second cathethus is shorter by 17.
  8. Pure quadratic equation
    kvadrat Solve pure quadratic equation ?.
  9. Hurry - rush
    bus_3 At an average speed 10 km/h I will come from the school to the bus stop for 29 minutes. How fast I need to go if I need to get to the bus stop in 21 minutes?
  10. Three digits number
    plot How many are three-digit integers such that in they no digit repeats?
  11. 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?
  12. Liters in cylinder
    cylinder_1 Determine the height at which level 20 liters of water in a cylindrical container having a bottom diameter 29 cm.
  13. Trapezoid RT
    lichobeznik2 The plot has a shape of a rectangular trapezium ABCD, where ABIICD with a right angle at the vertex B. side AB has a length 36 m. The lengths of the sides AB and BC are in the ratio 12:7. Lengths of the sides AB and CD are a ratio 3:2. Calculate consumptio
  14. Isosceles trapezoid
    rr_licho The lengths of the bases of the isosceles trapezoid are in the ratio 5:3, the arms have a length of 5 cm and height = 4.8 cm. Calculate the circumference and area of a trapezoid.
  15. Metal alloy
    ocel What is the ratio of metals in the alloy that is in the 50 tonnes of steel to 30 kg nickel?
  16. IS trapezoid
    el_trapezium Isosceles trapezoid arm measured 52 cm. Height is 44 cm and middle segment is 50 cm. Determine length of its bases.
  17. Basements
    Spider-and-Fly In the first basement is more flies than the spiders, the second vice versa. Each basement had spiders and flies together 100 feet. Determine how many could be flies and spiders in the first and second basement. PS. We only need, when you write how many.
  18. Wood
    rubanie_dreva Peter chops wood. If they cut down a half hours a day he ended work in 9 days. But Peter needs to end work 3 days earlier. How many minutes a day should cut down?
  19. Parallelogram
    quadrilateral_parallelogram The perimeter of the parallelogram is 202 cm. The length of one side is 1.2-times longer than the length of the shorter side. What is the length of sides of a parallelogram?
  20. Journey
    Mt-Everest The road from A to B measures 11.5 km. Firstly up the hill, then by level plane and then downhill. Tourist goes uphill at 3 km/h, on the plane 4 km/h and downhill 5 km/h. From point A to B went 2h 54 min back 3h 6 min. How long is the segment of level pla

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