Grade - examples - page 130

  1. Octahedron
    octahedron All walls of regular octahedron are identical equilateral triangles. ABCDEF octahedron edges have a length d = 6 cm. Calculate the surface area and volume of this octahedron.
  2. The result
    dice_2 How many times I decrease the number 1144 to get the result 22?
  3. Jam
    dzem Jar with jam weighs 800 grams. Jam weighs three times as much as the empty glass. What is the weight of jam that is in the glass?
  4. 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?
  5. Consecutive numbers
    progression Sum of ten consecutive numbers is 105. Determine these numbers (write first and last).
  6. Farmers
    zemedelec.JPG Farmers loaded into a truck of fruit and vegetables intended for the store. 10 boxes of 5 kg pears, 8 boxes of 6 kg plums, 7 boxes 9 kg of carrots and 10 bags of 50 kg of potatoes. How many kilograms of fruit and vegetables loaded in total? How many kg cou
  7. Unknown number 7
    percents2_9 16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number.
  8. Students
    cinema2 In the front row sitting three students and in every other row 11 students more than the previous row. Determine how many students are in the room when the room is 9 lines, and determine how many students are in the seventh row.
  9. MO 2016 Numerical axis
    osa Cat's school use a special numerical axis. The distance between the numbers 1 and 2 is 1 cm, the distance between the numbers 2 and 3 is 3 cm, between the numbers 3 and 4 is 5 cm and so on, the distance between the next pair of natural numbers is always in
  10. Timeage
    deep Seven times of my age is 8 less than the largest two-digit number. How old I am?
  11. Cuboid and ratio
    kvader Cuboid has dimensions in ratio 1:2:6 and the surface area of the cuboid is 1000 dm2. Calculate the volume of the cuboid.
  12. PIN - codes
    pin How many five-digit PIN - code can we create using the even numbers?
  13. Performance
    theathre Same number of tickets sold for 15 CZK, 20 CZK, 30 CZK and 40 CZK a total of CZK 13,230 on theatre performance. How many tickets were sold for this performance?
  14. Bus lines
    bus27 Buses connections are started from bus stop on its regular circuit as follows: No. 27 bus every 27 minutes and No.18 every half hour. What time started this two bus lines run if the bus stop met at 10:15 am.?
  15. The percentages in practice
    plodina If every tenth apple on the tree is rotten it can be expressed by percentages: 10% of the apples on the tree is rotten. Tell percent using the following information: a. in June rained 6 days b, increase worker pay 500 euros to 50 euros c, grabbed 21 fro
  16. Asymptote
    asymptote What is the vertical asymptote of ?
  17. One green
    gulicky In the container are 45 white and 15 balls. We randomly select 5 balls. What is the probability that it will be a maximum one green?
  18. Field on plan
    geodet sobrance Plan has a scale of 1: 2500.Determine dimensions in centimeters which will have on plan field with a length of 310 meters and a width of 182.5 meters.
  19. Sales of products
    cukriky_9 For 80 pieces of two quality products a total sales is 175 Eur. If the first quality product was sold for n EUR per piece (n natural number) and the second quality product after 2 EUR per piece. How many pieces of the first quality were sold?
  20. Brick
    tehla Brick weight before drying is 5.3 kg. After drying, the bricks is 1 kg lighter and after firing is 0.7 kg lighter than after drying. What is the weight of the brick after drying and firing?

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