Examples for 8th grade - page 112

  1. Banknotes
    penize How many different ways can the cashier payout € 310 if he uses only 50 and 20 euro banknotes? Find all solutions.
  2. Temperature conversion
    teplomer_12 The normal human body temperature is 98.6 degrees Fahrenheit. What is the temperature in degrees Celcius?
  3. Simplify 2
    expr Simplify expression: 5ab-7+3ba-9
  4. Inquality
    compare_4 Solve inequality: 3x + 6 > 14
  5. No smoke
    no_smoking Tobacco company NO-SMOKE adorned its stand at the cigarette-type trade fair with the cigarette-shaped. The dimensions of which were 20 times the size of a regular cigarette. The regular cigarette contains 0.8 mg of nicotine. How much nicotine would a giant
  6. Volume of ball
    ball1_5 Find the volume of a volleyball that has a radius of 4 1/2 decimeters. Use 22/7 for π
  7. Parallelogram
    kosodlznik3_1 Rhomboid (parallelogram) has a longer side of 50 cm long. The size of its one height is four times the size of its second height. Calculate the length of the shorter side of this rhomboid in the centimeters.
  8. Banknotes
    penize_49 Eva deposit 7800 USD in 50 banknotes in the bank. They had value 100 USD and 200 USD. How many were they?
  9. Reminder and quotient
    prime_4 There are given numbers A = 135, B = 315. Find the smallest natural number R greater than 1 so that the proportions R:A, R:B are with the remainder 1.
  10. Father and son
    family_16 Father and son weigh together 108kg. The father weighs 2.6 times more than his son. How much does weight my father and son count?
  11. An oil
    valec2_13 An oil drum is cut in half. One half is used as a water trough. Use the dimensions; length 82cm, width 56cm to estimate the capacity of the water trough in liters.
  12. Cows and calves
    cow_5 There are 168 cows and calves in the cowshed. Cows are in nine stalls and calves in four stalls. Same count cows are in every cow stall and three more in each calf stall than in a cow stall. What is the capacity of the stalls for cows and what for calves?
  13. Equations - simple
    linearna_1 Solve system of linear equations: x-2y=6 3x+2y=4
  14. Shopping center
    bicycle_gears_3 The shopping center buys from the manufacturer bikes at a purchase price of 180 €. It sells them for a sale price of 250 €. However, in the advertising for the sale of these goods, the shopping center spent 20% of the selling price of all bicycles in stock
  15. Two cubes
    cubes2 The surfaces of two cubes, one of which has an edge of 22 cm longer than the second are differ by 19272 cm2. Calculate the edge length of both cubes.
  16. Train speed
    trains_9 Two guns were fired from the same place at an interval of 10 minutes and 30 seconds, but a person in a train approaching the place hears second shot 10 minutes after the first. The speed of the train (in km/hr), supposing that sound travels at 340 m/s is:
  17. Supplementary angles
    susedne_huly One of the supplementary angles is larger by 33° than the second one. Calculate the angles size.
  18. Poplar
    topole How tall is a poplar by the river, if we know that 1/5 of its total height is a trunk, 1/10th of the height is the root and 35m from the trunk to the top of the poplar?
  19. Winch
    bubon The steel rope has a diameter of 6mm and a length of 20m. We are winding on drum width 60mm, starting diameter 50mm. What is the final diameter after winding?
  20. Dog price
    dog Tereza agreed to get a dog and 6000 crowns a year for help in a dachshund breeding station. After eight months she had to finish work and got a dog and 2000 crowns. What price does a dog have?

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