9th grade (14y) + direct relationship - examples

  1. Beer
    piva After three 10° beers consumed in a short time there are 7.4 g of alcohol in 5 kg adult human blood. How much is it per mille?
  2. Saving
    cars Kevin save € 4620 to buy a car. Yet it lacks save 65% of the car price. How much is the car?
  3. Road repair
    workers_1 Road repair took 16 days for 34 workers if they worked 6 hours a day. How many days take repair same road 33 workers if they work 6 per day?
  4. Bonus
    moeny Gross wage was 1113 USD including 16% bonus. How many USD were bonuses?
  5. Accidents
    nehoda-pomnik The count of accidents in 1993 caused 8009 women which is 7.1%. How many men caused the accidents?
  6. Copiers
    images Three copiers will do the same in an hour k copies. How many copies would be done in an hour by four such copiers? ?
  7. Division
    bonbons Three siblings Helena, Oliver and George split the bag with candies on merit in the ratio 1:6:3. How many candies should each get if in bag were 210?
  8. Pipes
    water_pipe Water pipe has a cross-section 1939 cm2. An hour has passed 567 m3 of water. How much water flows through the pipe with cross-section 300 cm2 per 14 hours if water flow same speed?
  9. Shadow and light
    stin Nine meters height poplar tree has a shadow 16.2 meters long. How long shadow have at the same time Joe if he is 1,4m tall?
  10. Server
    p_pro Calculate how many average minutes a year is the web server is unavailable, the availability is 99.99%.
  11. Cyclist
    1cyclist Cyclist goes uphill 1 km for 6.3 minutes and downhill minutes for 2.1 minutes, both applied to the pedals same force. How long he pass 1 km by plane?
  12. Pediatrician
    doctor Pediatrician this month of 21 working days takes 3 days holidays. What is the probability that on Monday will be at work?
  13. Radians
    pi_text Convert 54° to radians. Write result as multiple of number π.
  14. Train and car
    car_vs_train The train and the car started at a constant speed to journey. When the train travels 78 km, the car travels 64 km. How many km travels the train when the car travels 78 km?
  15. Scale
    pool_1 Swimming pool is long 110 m and 30 m wide. The plan of the city is shown as a rectangle with area 13200 cm2. What scale is the city plan?
  16. Gear
    ozubene_kolesa Two gears, fit into each other, has transfer 1:5. Centres of gears are spaced 28 cm. What are the radii of the gears?
  17. Tmp workers
    profesiadays Three temporary workers cleaned 60 m of walkway in 5 hours. How many meters of the walkway cleared seven volunteers for eight hours?
  18. Copy typist
    pisaci_stroj Typist for 12 hours rewritten 15% of the manuscript. After how many hours he will done 35% of the manuscript?
  19. Pool
    pool If water flows into the pool by two inlets, fill the whole for 9 hours. First inlet filled pool 8 hour longer than second. How long pool is filled with two inlets separately?
  20. 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:

Do you have interesting mathematical example that you can't solve it? Enter it and we can try to solve it.



To this e-mail address we will reply solution; solved examples are also published here. Please enter e-mail correctly and check whether you don't have a full mailbox.