Examples for 9th grade - page 49

  1. One percent
    led One percent of all the lights in the city are LED, the remaining 99% are conventional. Other types are not there. John counted them honestly but he had counted only conventional. After a good dinner he registered numbers and he have notice that from all t
  2. Baskets of apples
    jablka_3 Grandfather gathered apples into baskets. He filled one large and three small baskets. Small baskets are identical and each can hold 3 kg of apples less than in a large basket. In small baskets together 3 kg of apples over a large basket. How many kilogram
  3. Ravens
    havrany On two trees sitting 17 ravens. If 3 ravens flew from first to second tree and 5 ravens took off from second tree then the first tree has 2 times more ravens than second tree. How many ravens was originally on every tree?
  4. Average speed
    earth_2 What is the average speed you have to move the way around the world in 80 days? (Path along the equator, round to km/h).
  5. Sales off
    lacnejsie shoes cost x euros. First they are discounted by 50%, and then 25% of the new amount. Determine what percentage of the total cost is cheaper.
  6. Water wessel
    karafa The vessel containing water has a weight 19 kg. After pouring half the water its weigth 11 kg. What is the weight of the empty vessel?
  7. Price increase 2x
    percents_3 If two consecutive times we increase the price of the product by 20%, how many % is higher final price than the original?
  8. Euclid theorems
    euklidova_veta_trojuhelnik_nakres Calculate the sides of a right triangle if leg a = 6 cm and a section of the hypotenuse, which is located adjacent the second leg b is 5cm.
  9. The factory
    hutny material The factory ordered 500 hexagonal steel bars of square section with 25 mm side. How many cars with a load capacity of 3 tonnes will be needed for bars move if the steel density is 7,850 kg.m-3?
  10. Copper wire
    cu_wire_1 What is the weight of 1000 m copper wire with a diameter of 5 mm when rezistivity p = 8.8 g / cm3?
  11. Cuboid and ratio
    kvader Cuboid has dimensions in ratio 1:2:6 and the surface area of the cuboid is 1000 dm2. Calculate the volume of the cuboid.
  12. Body diagonal
    cubes3_1 Find the cube surface if its body diagonal has a size of 6 cm.
  13. Salary in enterprise
    1000czk The average salary in the company is 27 000 CZK, 30% of workers have the lowest average income of 19 thousand CZK. There were an increase in the salary in this group by 2%. How much % increased the average salary across the company?
  14. Centre of mass
    centre_g_triangle The vertices of triangle ABC are from the line p distances 3 cm, 4 cm and 8 cm. Calculate distance from the center of gravity of the triangle to line p.
  15. Car
    sanitka_1 Car goes some distance in 3 hours and 20 minutes. If it increase speed by 10 km/h, i goes this distance in 2.5 hours. Calculate the distance.
  16. Hexagon = 8 parts
    stef.6.11.99 Divide the regular hexagon into eight equal parts.
  17. Saving
    2kc Paul save 155Kč in 46 2 Kc and 5Kc coins. How much saved 2Kc and 5Kc coins?
  18. Bob and Bobek
    bob_a_bobek At 10h 20min runs Bobek from hat at average speed 12 km/h. At what time must run out Bob at speed 18 km/h to catch him 9 kilometers from the hat?
  19. Barrel 4
    sudy Barrel of water weighs 63 kg. After off 75% water, the weight of the barrel with water is 21 kg. How many kg weigh empty barrel and how many kgs water in it?
  20. Savings and retirement
    babky_1 The older sibling has saved 44% more euros than the youngest, which represents 22 euros. How many euros older brother has saved ?

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