Examples for 9th grade

  1. Triangular prism
    prism3_1 Calculate the volume and surface area of a triangular prism if it is given: a = 6.8 dm. ..Va = 4 dm. (base edge length and base triangle height length) ... ... .v = 23 dm (body height)
  2. Six on dice
    dices2_1 What is the probability that when throwing two dice will fall at least one six?
  3. Largest angle of the triangle
    triangle_1111_2 What is the largest angle of the triangle if the second angle is 10° greater than twice the first and the third is 30° smaller than the second?
  4. Outer angles
    triangle_1111_3 The outer angle of the triangle ABC at the A vertex is 71°40 ' outer angle at the vertx B is 136°50'. What size has the inner triangle angle at the vertex C?
  5. Perimeter of triangle
    rt_triangle_1 In triangle ABC angle A is 60° angle B is 90° side size c is 15 cm. Calculate the triangle circumference.
  6. Sum or product
    dice_6 What is the probability that two dice fall will have the sum 7 or product 12?
  7. Sum on dice
    dices2 We have two dice. What is the greater likelihood of fall a total sum 7 or 8 ? (write 7, 8 or 0 if the probabilities are the same)?
  8. Cross section
    trapezium_right The cross-section ABCD of a swimming pool is a trapezium. Its width AB=14 meters, depth at the shallow end is 1.5 meters, and at the deep end is 8 meters. Find the area of the cross-section.
  9. Isosceles triangle
    pomer_triangle The perimeter of an isosceles triangle is 112 cm. The length of the arm to the length of the base is at ratio 5:6. Find the triangle area.
  10. Diagonal 20
    plaza Diagonal pathway for the rectangular town plaza whose length is 20 m longer than the width. if the pathway is 20 m shorter than twice the width. How long should the pathway be?
  11. Three-digit
    seven How many three-digit natural numbers do not have the number 7?
  12. Cube surface area
    cubes2_2 The surface of the cube was originally 216 centimeters square. The surface of the cube has shrunk from 216 to 54 centimeters sq. Calculate how much percent the edge of the cube has decreased.
  13. Lines
    lines_4 How many lines can be draw with 8 points, if three points lie on one line and the other any three points do not lie on the same line?
  14. ICE train
    ice_train German runways test a new ICE train between Munich and Berlin. The train runs to Berlin at a slow speed of 100 km/h. Back from Berlin goes faster. How quickly did the train have to go on a return trip so that the total average train speed for both journey
  15. Book read
    books_12 If Petra read 10 pages per day, she would read the book two days earlier than she read 6 pages a day. How many pages does a book have?
  16. Digits
    numbers_48 How many five-digit numbers can be written from numbers 0.3,4, 5, 7 that is divided by 10 and if digits can be repeated.
  17. Cube wall
    cubes_16 Calculate the cube's diagonal diagonal if you know that the surface of one wall is equal to 36 centimeters square. Please also calculate its volume.
  18. Two numbers
    fractal_6 The sum of the two numbers is 1. Find both numbers if you know that half of the first is equal to one seventh of the second number.
  19. Ratio of two unknown numbers
    numbers2_23 Two numbers are given. Their sum is 30. We calculate one-sixth of a larger number and add to both numbers. So we get new numbers whose ratio is 5:7. Which two numbers were given?
  20. Mason with assistant
    workers_15 Mason had to complete the work in 10 days. Two and a half days later his assistant arrived. Together they completed the work in next three and a half days. How many days would he need an assistant for the same work?

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