Examples for 7th grade (seventh) - page 12

  1. Mailbox
    post Mailbox is opening at regular intervals 3 times a day. The first time is opened at 8:00 and the last at 19:00. Calculate hours when mailbox is opened during day.
  2. Three workers
    three_workers Three workers A, B, C have to work on a specific task. Workers A and B completed whole task in 11 days, B together with C for 15 days, A together with C for 24 days. How long it would take to complete the task every one of them alone? How long it would.
  3. Steamship
    parnik Between the two ports on the river is going steamship. The journey there and back takes 8:42. Downstream steamship traveling at 20 km/h, upstream 9 km/h. What is the distance between the ports?
  4. Leveling
    quattro Calculate how many 25 kg bags of leveling concrete must be purchased if we leveling room 15 m2 to the "height" 6 mm if consumtion is 1.5 kg per square meter and millimeter thickness.
  5. Blueberries
    boruvky Marie earns 3 liters of blueberries for 3.4 hours, Peter 2.4 liters for 2.9 hours. How long have earns together one liter?
  6. XY triangle
    triangle Determine area of triangle given by line 7x+8y-69=0 and coordinate axes x and y.
  7. Christmas Day
    stedryd In leap years was 53 Sundays. On what day of the week fell to Christmas Day?
  8. Coin and die
    die Flip a coin and then roll a six-sided die. How many possible combinations are there?
  9. Day
    clock_1 What part of the day is 23 hours 22 minutes? Express as a decimal number.
  10. Parallelogram
    rovnobeznik Calculate the area and perimeter of a parallelogram whose two sides are long a=18 cm b=12 cm and height ha = 2 cm long.
  11. Mouse Hryzka
    myska_hryzka Mouse Hryzka found 27 identical cubes of cheese. She first put in a large cube out of them and then waited for a while before the cheese cubes stuck together. Then from every wall of the big cube she will eats the middle cube. Then she also eats the cube
  12. Divisibility
    dots Determine the smallest integer which divided 11 gives remainder 4 when divided 15 gives remainder 10 and when divided by 19 gives remainder 16.
  13. Fuel consumption
    1car Kia car has an average diesel consumption of 4.9 liters per 100 kilometers. What is the car range for a full tank of volume 50 liters?
  14. Pumps
    water_pump Pump that draws water at velocity 3.5 liters per second water from a construction trench take 35 minutes. a) Find out how many minutes the water would run out of the trench pump that draws 7.4 liters of water per second. b) What is the pumping velocity wo
  15. Compass
    wind_rose What angle are between directions WSW (WestSouthWest) and SSE (SouthSouthEast) on the compass?
  16. Drunk man
    drunk-man Drunkman has 1.6‰ of alcohol in the blood. How many grams of alcohol has in blood, if he have 7 kg of blood?
  17. Ratio
    pomer Increase in the ratio 20:4 number 18.5.
  18. AVG of INT
    seq_moon What is the average of the integers from 9 throuht 52 inclusive?
  19. Lid
    drywell What is the weight of concrete cover (lid) to round shape well with a diameter 1.8 m, if the thickness of the cover is 11 cm? 1 m3 of concrete weighs 2190 kg.
  20. Lines
    bus Five bus lines runs at intervals 3, 6, 9, 12, 15 minutes. In the morning, suddenly start at 4:00. After how many minutes the bus lines meet again?

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