Examples for 8th grade - page 36

  1. Ski lessons
    skiing_2 On the ski course leaves 80 pupils. They live in triple and quadruple rooms. Count if rooms is the 23. How many are triple and quadruple rooms?
  2. Sportsman
    lungs A trained athlete is able to exhale after a deep breath still 500 ml of air. At normal inhalation and exhalation is breathing 500 ml of air. Within one minute, one breath and exhaled 19 times. What part of breathing air per day is one exhalation?
  3. Typing course
    typewriter_1 Before taking a typing course, Seth could type 30 words per minute. By the end of the course, he was able to type 66 words per minute. Find the percent increase.
  4. Squaring the Circle
    SquareCircle Calculating side of the square with the same area as the circle of radius 18.
  5. Hands
    soviet_watch The clock shows 12 hours. After how many minutes will agle between hour and minute hand 80°? Consider the continuous movement of both hands hours.
  6. Bath
    bathroom In the bath is 30 liters of hot water. Then added 38 liters of cold water at temperature of 17 °C decreased temperature of water to 48 °C. What was the initial temperature of the hot water?
  7. Subway
    metro Subway train went between two stations that gradually accelerated for 20 seconds and reached a speed of 80 km/h. At this rate, went 41 seconds. Then 17 seconds slowed to a stop. What was the distance between the stations?
  8. Three workers
    eura_6 Three workers got paid for work. First earn € 50, the second € 100 and third € 60. For further work should receive together € 735. How do you divide that amount in order to be distributed in the same proportion as the first job?
  9. Dried apples
    jablka_2 How many kilograms of fresh apples id needed to 120 kg of dried apples when from 0.4 tons of fresh apples we get 75 kg of dried apples?
  10. Three children
    chocholate_1 3 children eat 8 chocolates in 6 days. How many chocolates 6 children eat in 18 days?
  11. Money duo
    money_18 Julius and Mark have together 45 euros. Mark has 50% more money than Julius. Determine the amount of money that have Mark and Julius.
  12. Cylinder twice
    valec_3 If the radius of the cylinder increases twice, and the height is reduced twice, then the volume of the cylinder increases (how many times?):
  13. 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.
  14. Ages
    age2_1 John, Teresa, Daniel and Paul have summary 56 years. Their ages are in a ratio of 1:2:5:6. Determine how many years have each of them.
  15. Diagonal - simple
    makac Calculate the length of the diagonal of a rectangle with dimensions 5 cm and 12 cm.
  16. Buttons
    knofliky Shirt has 6 buttons, blouse has 4 buttons. All buttons are 176. Shirts and blouses are together 36. How many are the shirts and blouses?
  17. Painter 3
    painter_2 Dad want to paint wall high 250 cm wide and 230 cm with wallpaper. How many meters must buy wallpaper if wallpaper width is 60 cm?
  18. Brackets
    brackets Place one pair of brackets in expression 20-16 + 10 - 4 - 2 so that the result will be 0.
  19. Roof tiles
    Lichobeznik_strecha The roof has a trapezoidal shape with bases of 15 m and 10 m, height of roof is 4 meters. How many tiles will need if on 1 m2 should be used 8 tiles?
  20. Three friends
    pizza_4 Divide 570 euros to three friends so that first will get 50 euros less than the second and third twice more than the first. How many euros will get everyone?

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