Examples for 8th grade - page 27

  1. 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.
  2. Car inflation
    car_1 About what percentage price of car increased if price rose from €1880 to €2200?
  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. 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?
  5. 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
  6. Earth's diameter
    om5960-v2 The Earth's diameter on the equator is approximately 12750 km. How long does the Gripen flyover the Earth above the equator at 10 km if it is at an average speed of 1500 km / h?
  7. Diamond
    rhombus2_2 Determine the side of diamond if its content is S = 353 cm2 and one diagonal u2 = 45 cm.
  8. 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?
  9. Triangle
    Triangle_trig Calculate the sides of the triangle if its area S = 630 and the second cathethus is shorter by 17.
  10. Three digits number
    plot How many are three-digit integers such that in they no digit repeats?
  11. 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.
  12. Sun rays
    sfinga-a-cheopsova-pyramida-w-4066 If the sun's rays are at an angle 60° then famous Great Pyramid of Egypt (which is now high 137.3 meters) has 79.3 m long shadow. Calculate current height of neighboring chefren pyramid whose shadow is measured at the same time 78.8 m and the current hei
  13. 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.
  14. Metal alloy
    ocel What is the ratio of metals in the alloy that is in the 50 tonnes of steel to 30 kg nickel?
  15. 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
  16. 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?
  17. 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.
  18. Pure quadratic equation
    kvadrat Solve pure quadratic equation ?.
  19. Baker
    pekar The baker makes from 10 kg of flour 12 kg dough. How much flour he need to make a 100 kg dough?
  20. Cuboid
    dodecagon The volume of the cuboid is 245 cm3. Each cuboid edge length can be expressed by a integer greater than 1 cm. What is the surface area of the cuboid?

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