Grade - examples - page 80

  1. Pencils
    pencils Emil has 23 pencils in a pencil case, 18 of which were broken. Emily 9 trims, 2 breaks, 4 trims and goes to school. When he return from school, he has broken 5 pencils. How many pencils have trimed at school?
  2. Cube corners
    polyhedra-truncated-cube From cube of edge 14 cm cut off all vertices so that each cutting plane intersects the edges 1 cm from the nearest vertice. How many edges will have this body?
  3. Motor oil
    olej 30 liters of oil cost 28.80 Euros. How much cost a liter?
  4. Right angled triangle 2
    vertex_triangle_right LMN is a right angled triangle with vertices at L(1,3), M(3,5) and N(6,n). Given angle LMN is 90° find n
  5. Buses
    regiojet Buses Ikarus and Karosa simultaneously started at 8:00 from the final station. Ikarus is returned to the station after 30 minutes. Karosa after 45 minutes. At what time both buses again returned to the station?
  6. Sails
    ship_nina We known heights 220, 165 and 132 of sail. It has triangular shape. What is the surface of the sail?
  7. Container with water
    water_2 The weight of a container with water is 2.48 kg. If the cast 75% water, the container with water has a weight of 0.98 kg. Determine the weight of the empty container. How much water was originally in the container?
  8. Numbers
    number_line Find number on thenumber line that has same distance from this numbers:
  9. Triangle ABC
    squares4 Triangle ABC has side lengths m-1, m-2, m-3. What has to be m to be triangle a) rectangular b) acute-angled?
  10. Chess
    chess How many different ways can initiate a game of chess (first pass)?
  11. The city 2
    kingkong Today lives 167000 citizens in city. How many citizens can we expect in 11 years if their annual increase is 1%?
  12. Bathroom
    koupelna How many CZK we pay for lining the perimeter walls of the bathroom with rectangular shape with dimensions 3.5 m and 4 m, high 1.5 m if 1 square m tile cost 300 CZK?
  13. Pool 3
    basen_3 How long will fill pool cuboid shape (8m 6m 1.5m) when flows 15 liters/s?
  14. College
    harvard At the college are at 57 rooms 194 students. Some rooms are triple and some quad. How many triple and quadruple rooms there is, if it is all fully occupied?
  15. Rings groups
    venn 27 pupils attend some group; dance group attends 14 pupils, 21 pupils sporty group and dramatic group 16 pupils. Dance and sporting attend 9 pupils, dance and drama 6 pupil, sporty and dramatic 11 pupils. How many pupils attend all three groups?
  16. Plums
    plumbs In the bag was to total 136 plums. Igor took 3 plums and Mary took 4/7 from the rest. How many plums remained in the bag?
  17. A three-digit numbers
    clocks_1 Determine the total number of positive three-digit numbers that contain a digit 6.
  18. Divisibility 2
    divisors How many divisors has integer number 13?
  19. Water reservoir
    nadrz_1 The water reservoir is filled through one inlet 4 hours later than both together, then another inlet 9 hours later than both together. For how long is filled by each separately?
  20. Colors
    peracnik Willie got birthday 6 colour pens in different colors. How many ways he can give them side by side in pencil?

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