Examples for 9th grade - page 66

  1. Seamstress 2
    krajcirka_1 Seamstress bought two kinds of textile in whole meters. One at 50 SKK and the second 70 SKK per meter. How many meter bought from this two textiles when paid totally 1540 SKK?
  2. Quadrangular prism
    hranol4sreg_7 Calculate the volume and surface area of a regular quadrangular prism 35 cm high and the base diagonal of 22 cm.
  3. Forces
    resultant_force Determine the resultant of two perpendicular forces F1 = 560 N and second force of 25% smaller.
  4. Three ints
    2016_hny The sum of three consecutive integers is 2016. What numbers are they?
  5. Mom and daughter
    family_1 Mother is 39 years old. Her daughter is 15 years. For many years will mother be four times older than the daughter?
  6. The factory
    hutny material The factory ordered 500 hexagonal steel bars of square section with 25 mm side. How many cars with a load capacity of 3 tonnes will be needed for bars move if the steel density is 7,850 kg.m-3?
  7. Pentagon
    5gon Calculate the length of side, circumference and area of a regular pentagon, which is inscribed in a circle with radius r = 6 cm.
  8. Ten dices
    dices_3 When you hit ten dices at the same time you get average 35. How much do you hit if every time you get six, you're throwing the dice again?
  9. Rectangle
    diagonal_rectangle_2 The rectangle has a perimeter 75 cm. Diagonal length is 32.5 cm. Determine the length of the sides.
  10. Two cyclists
    compass_1 Two cyclists started from crossing in the same time. One goes to the north speed 20 km/h, the second eastward at speed 26 km/h. What will be the direct distance cycling 30 minutes from the start?
  11. Ski tow
    ski_tow The ski club has 168 pupils and used lift with 60 seats, while students always follow the same sequence in filling seats. How many times while riding a ski lift skier sitting in the same seat as the first run?
  12. Sweets
    Caramelos We want to prepare 5 kg of sweets for 150 CZK. We will mix cheaper candy: 1 kg for 120 CZK and more expensive candy: 1 kg per 240 CZK. How much of this two types of candy is necessary to prepare this mixture?
  13. Mirror
    mirror How far must Paul place a mirror to see the top of the tower 12 m high? The height of Paul's eyes above the horizontal plane is 160 cm and Paul is from the tower distant 20 m.
  14. Unknown number 7
    percents2_9 16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number.
  15. Mr and Mrs
    clocks2_8 Mr. Calda and Mrs. Cald have a total of 139 years. How many years have when we know that Mr. Calda is 9 years older than Mrs. Cald
  16. Sales stores
    map_2 The first sales store passed the 1/3 and the second 2/5 of the total amount of goods.In third store passed the 2/3 rest of the goods. The remaining 40 kg of goods put into fourth store. How many kilograms of goods pass to a third store?
  17. Umbrella
    dazdnik Can umbrella 75 cm long fit into a box of fruit? The box has dimensions of 390 mm and 510 mm.
  18. Parking
    bus_and_car 120 vehicles parking on the morning. Pasenger car is charged 20 CZK, 50 CZK per bus. The guard collected for parking 2640 CZK in total. How many cars and how many buses stood in the parking?
  19. Hydrochloric acid
    hcl Determine the concentration of which must have a solution of hydrochloric acid that mixing 10 l of the solution with 8 liters of 26% solution to get the solution with a concentration of 50%?
  20. Pears
    hrusky Andrew, Lenka and Rasto have together 232 pears. Lenka has 28 more than Rasto and Rasto pears have 96 more than Andrew. Determine how much each of them has pears.

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