Examples for 7th grade (seventh) - page 18

  1. 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?
  2. Car inflation
    car_1 About what percentage price of car increased if price rose from €1880 to €2200?
  3. 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?
  4. Potatoes
    potatoes Could 446 tons of potatoes (ρ = 771 kg/m³) fits in a warehouse with a volume of 699 m³ ?
  5. 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?
  6. 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.
  7. Pure quadratic equation
    kvadrat Solve pure quadratic equation ?.
  8. Chase
    pavel_007 Paul travel at 60 km/h. After 18 km ride found that he forgot an important book. His brother Thomas behind him carrying it. How fast must Thomas go to catch up with Paul in 31 minutes?
  9. 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.
  10. Pumps
    fuel_tank 6 pump fills the tank for 3 and a half days. How long will fill the tank 7 equally powerful pumps?
  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. 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
  13. 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?
  14. 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
  15. 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?
  16. Tablecloth
    decka I embroider tablecloth in 20 days but if I embroider 3/4 hours a day I have embroider it for 15 days. How long do I embroider a day?
  17. 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:
  18. Aircraft
    aircraft_soviet The aircraft has in a fuel tank 68 hl of aviation fuel and flight consumes 3.6 liters of fuel. Identify the function, which expresses the dependence of the volume of fuel in tank on the track distance plane flew by. How many hectolites of fuel is still in
  19. David number
    numbers2_4 Jana and David train the addition of the decimal numbers so that each of them will write a single number and these two numbers then add up. The last example was 11.11. David's number had the same number of digits before the decimal point, the Jane's number
  20. Eggs
    eggs_1 Mother bought from neighbors 39 domestic eggs. Her neighbor got back €4.54 from €10. How many euros get back from 20 banknote if she buy 94 eggs from a neighbor?

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