Examples for 9th grade - page 10

  1. Percent chaining
    meter_1 Calculate 20% from 70% from 80 km
  2. Solutions
    bilde How much 60% solution and how much 35% solution is needed to create 100 l of 40% solution?
  3. Digging companies
    companies Company A would dig a pit for 12 days, company B for 15 days, company C for 20 days and the company D for 24 days. Work began together companies C and D, but after three days joined them other two companies. How long took to dig a pit?
  4. Spherical cap
    kulova_usec From the sphere of radius 12 was truncated spherical cap. Its height is 4. What part of the volume is spherical cap from whole sphere?
  5. Pediatrician
    doctor Pediatrician this month of 21 working days takes 3 days holidays. What is the probability that on Monday will be at work?
  6. Sales off
    sweater If a sweater sells for $ 12 after a 25% markdown, what was its original price?
  7. Prism
    prism-square The lenght, width and height of a right prism are 18, 14 and 9 respectively. What is the lenght of the longest segment whose endpoints are vertices of the prism?
  8. Compass
    wind_rose What angle are between directions W (West) and SE (SouthEast) on the compass?
  9. Oil rig
    oil_rig_tower Oil drilling rig is 23 meters height and fix the ropes which ends are 8 meters away from the foot of the tower. How long are these ropes?
  10. Cosine
    cosine The point (21, 20) is on the terminal side of angle θ. cos θ = ?
  11. Components
    components In the box are 6 white, 4 blue and 2 red components. What is the probability that we pull one white, one blue and one red component without returning?
  12. Metals
    metals_2 In the Hockey World Cup play eight teams, determine how many ways can they win gold, silver and bronze medals.
  13. 4 pipes
    roury The tank flows out by 4 pipes in 6 hours 120 hl water. How much water flows out of 5 pipes of the same diameter in 14 hours?
  14. Cars plates
    car_plate How many different licence plates can country have, given that they use 3 letters followed by 4 digits?
  15. Discount
    sales_discount Product has been discounted twice by 14%. What is the total discount given?
  16. Cylinder - A&V
    cylinder The cylinder has a volume 253. The base has a radius 5. What is the area of surface of the cylinder?
  17. Family
    4kids Family has 4 children. Ondra is 3 years older than Matthew and Karlos 5 years older than the youngest Jane. We know that they are together 30 years and 3 years ago they were together 19 years. Determine how old the children are.
  18. Euclid 5
    euclid_3 Calculate the length of remain sides of a right triangle ABC if a = 7 cm and height vc = 5 cm.
  19. Racing track
    racing_track On the racing track circling three cars. The first passes one circuit for 8 seconds, the second for 16 seconds and a third for 15 seconds. a) Calculate number of seconds since the start to catch all three cars together for the first time again across the.
  20. Spherical segment
    circular_segment_1 Spherical segment with height h=8 has a volume V=294. Calculate the radius of the sphere of which is cut this segment.

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