New math problems - page 14

  1. Glass
    pohgar How many glass are needed to produce glass with base regular 5-gon if one base triangle in the base is 4.2 square cm and the height is 10 cm?
  2. Z9-I-4
    numbers_30 Kate thought a five-digit integer. She wrote the sum of this number and its half at the first line to the workbook. On the second line wrote a total of this number and its one fifth. On the third row she wrote a sum of this number and its one nines. Fi
  3. Tunnels
    Mysky Mice had built an underground house consisting of chambers and tunnels: • each tunnel leading from the chamber to the chamber (none is blind) • from each chamber lead just three tunnels into three distinct chambers, • from each chamber mice can get to any
  4. Diagonal of the rectangle
    rectangle_1 Calculate the diagonal of the rectangle which area is 54 centimeters square and the circuit is equal to 30 cm.
  5. Average speed
    earth_2 What is the average speed you have to move the way around the world in 80 days? (Path along the equator, round to km/h).
  6. Content area and percents
    squares_8 Determine what percentage is smaller cube surface, when the surface area of the wall decreases by 25%.
  7. Fluid
    nadoby We have vessels containing 7 liters, 5 liters and 2 liters. Largest container is filled with fluid the others empty. Can you only by pouring get 5 liters and two 1 liter of fluid? How many pouring is needed?
  8. Cuboid enlargement
    cubes_12 By how many percent increases the volume of cuboid if its every dimension increases by 30%?
  9. Cube 5
    cubes_10 The content area of one cube wall is 32 square centimeters. Determine the length of its edges, its surface and volume.
  10. Third member
    seq_6 Determine the third member of the AP if a4=93, d=7.5.
  11. Cube edge
    cubes_9 Determine the edges of the cube when the surface is equal to 37.5 cm square.
  12. Pet store
    fish In a pet store, they are selling out the fish from one aquarium. Ondra wanted half of all fish, but they don't wish cut by hal fany fish he got one more than demanded. Matthew wished the remaining half of the fish, but as Andrew got half the fish more th
  13. Three friends
    money_19 Three friends divided the profit 104,650 CZK, so that for every 4 CZK, which got the first friend equals 5 crowns for second and for every 9 CZK, which got the second equals 16 CZK for third. Question: Who got the most and how much.
  14. Billiard balls
    balls_billiard A layer of ivory billiard balls of radius 6.35 cm is in the form of a square. The balls are arranged so that each ball is tangent to every one adjacent to it. In the spaces between sets of 4 adjacent balls other balls rest, equal in size to the original. T
  15. Cacao
    chocholate_2 Cacao contains 34% filling. How many grams of filling are in 130 g cacao.
  16. Unknown number 7
    percents2_9 16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number.
  17. Three children
    chocholate_1 3 children eat 8 chocolates in 6 days. How many chocolates 6 children eat in 18 days?

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