Examples for 8th grade - page 41

  1. Triangle SAS
    triangle_iron Calculate area and perimeter of the triangle, if the two sides are 19 cm and 80 cm long and angle them clamped is 90°.
  2. Apples
    jablka_4 Apples I picked 600 kg this year. Autumn's apples was 4 times more than the summer. How many kg's I picked the summer and how much winter apples?
  3. Cruise liner
    parnik_1 Cruise liner runs along the river between points A and B. The journey downstream takes 40 minutes 1 hour upriver. The flow rate of the river is 3 km/h. What is the speed of cruise liner?
  4. Unknown number 7
    percents2_9 16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number.
  5. Cancer
    cancer Of the 80 people 50 people ill cancer. What percentage of people isn't ill?
  6. Cargo
    tractor_lorry Car with cargo weight 7610 kg. Weight of car is 23% of the total weight of car and cargo. How heavy is cargo?
  7. Interst on savings
    ecb_2 The bank offers 1.6% interest. How many euros have to insert at the beginning if we received € 15 on the interest?
  8. Factory
    factory_1 In the factory workers work in three shifts. In the first inning operates half of all employees in the second inning and a third in the third inning 200 employees. How many employees work at the factory?
  9. Canister
    kanister Gasoline is stored in a cuboid canister having dimensions 44.5 cm, 30 cm, 16 cm. What is the total weight of a full canister when one cubic meter of gasoline weighs 710 kg and the weight of empty canister is 1.5 kg?
  10. Cenda and Pepa
    suchacky Cenda and Pepa went to the event. Cenda started alone. Canda started after him for 20 minutes. How long took Cenda to catch him? Cenda traveling at 15 km/h, and Pepa traveling at 25 km/h.
  11. Bottles
    lahve Mrs. Violet brewed 15 l of raspberry juice. She poured it into 17 bottles. Some were 3/4 liter and some one liter. How many was bottles of this two types?
  12. Tonic
    krem One package tonic consume Mom 12 weeks and daughter for 14 weeks. 4 weeks they use the same cream together and then only daughter. How many weeks endured tonic to daughter then?
  13. Pedestrian and the cyclist
    cyklista_1 Pedestrian and cyclist went against each from the two cities that are distant 40 km. Pedestrian started 30 minutes before the cyclist and walk an average speed of 5 km/h. What speed went cyclist when met after 120 minutes from the start of the pedestrian?
  14. Euros
    bicycles Peter, Jane and Thomas have together € 550. Tomas has 20 euros more than Jane, Peter € 150 less than Thomas. Determine how much has each of them.
  15. Euros
    fractal_1 Michal, Peter, John and Lenka got together 2,400 euros. They share an amount in ratio 2:6:4:3. How many got each of them?
  16. Work at plant
    workers_4 Handyman has vowed to do repair work at the plant for 25 days. However, work had to be shortened and therefore gained helper. Together they made all the corrections for 13 1/3 days. How long the work would take helper himself?
  17. Lathe
    sustruh Calculate the percentage of waste if the cube with 52 cm long edge is lathed to cylinder with a maximum volume.
  18. Cube 7
    krychle_4 Calculate the volume of a cube, whose sum of the lengths of all edges is 276 cm.
  19. Apples 2
    apples_2 How many apples were originally on the tree, if the first day fell one third, the second day quarter of the rest and on tree remained 45 apples?
  20. Principal and interest
    bank_pig Peter put € 270 principal into bank and at the end of the year on account was € 282. To what annual interest rate that Peter had deposited money in the bank?

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