Examples for 8th grade - page 14

  1. Buses
    regiojet Buses Ikarus and Karosa simultaneously started at 11:00 from the final station. Ikarus is returned to the station after 30 minutes. Karosa after 45 minutes. At what time both buses again returned to the station?
  2. Washing machine
    washing_masine The price of washing machine was decreased by 24% and then by 59 € due small sales. After two price decreases cost € 300. How much was originally cost?
  3. Ladislav in Amsterdam
    jakob3 Ladislav was reward and went to conference in Amsterdam. Conferense fee was € 2184. Calculate how many books Ladislav could buy at the price of 42 and 28 euros if he don't want fill whole home library and he can buy only 63 books?
  4. Arm
    arm Calculate the length of the arm r of isosceles triangle ABC, with base |AB| = 16 cm and a height v=10 cm.
  5. Newton's task
    cow Grass grows in the meadow equally fast and evenly. It is known that 58 cows graze meadow for 30 days and 80 cows by 19 days. How many cows graze meadow for 6 days?
  6. Hole
    cube_w_hole In the center of the cube with edge 15 cm we will drill cylinder shape hole. Volume of the hole must be 28% of the cube. What drill diameter should be chosen?
  7. Bits, bytes
    bits Calculate how many different numbers can be encoded in 16-bit binary word?
  8. Harvesters
    kombajny The first harvester reaps the grain from land for 24 hours, the second harvester for 16 hours. For how many hours will take harvest by two harvesters, but the second harvester started working four hours later than the first?
  9. Gloves
    rukavice I have a box with two hundred pieces of gloves in total, split into ten parcels of twenty pieces, and I sell three parcels. What percent of the total amount I sold?
  10. Gold coin
    gold_munzen Gold coin contains 963 promile pure gold, which is 8.39 g. What is the weight of coin in grams?
  11. Strawberries
    strawberries Father collects strawberries himself in 4 hours, son in 10 hours. How long will it take them along when dad comes to help son collect strawberries after 4 hours?
  12. Scouts
    skauti_1 The boys from scout group traveled 3 days distance 105 km. Every day walked 1.3 km less than the previous day. How many kilometers scouts walked in the first day?
  13. Painters
    painters The first team of painters would paint bridge in 15 days, the second in 10 days. After 3 days of working together second team goes out and continue only first team. How many days took second team to finish painting the bridge?
  14. Climb
    aircraft_ascend For horizontal distance 3 km road rise by 5.4 m. Calculate the road pitch in ‰ (permille, parts per thousand).
  15. Inflow - outflow
    water_barrels The tank will fill by inflow for 93 minutes and empties by outflow for 104 minutes. How long take to fill tank if it is also opened the inflow and outflow?
  16. Divisors
    one Find all divisors of number 418. How many are them?
  17. Degrees to radians
    angle Convert magnitude of the angle α = 618°40'29" to radians:
  18. Two pumps
    nadrz_4 The first pump fills the tank in 24 hours second pump in another 40 hours. For how long will take fill the tank if operate both pumps at the same time?
  19. Volleyball
    volejbal 8 girls wants to play volleyball against boys. On the field at one time can be six players per team. How many initial teams of this girls may trainer to choose?
  20. Apples 2
    jablko James has 13 apples. It has 30 percent more apples than Sam. How many apples has Sam?

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