The most difficult problems

  1. Tetrahedral pyramid
    ihlan Determine the surface of a regular tetrahedral pyramid when its volume is V = 120 and the angle of the sidewall with the base plane is α = 42° 30´.
  2. Possible lengths
    triangles Find the most possible lengths for the third side of a triangle with sides 20 and 18.
  3. Find the 12
    circle_eq Find the equation of the circle with center (3,7) and circumference 8π units.
  4. Hexagonal pyramid
    hex_pyramid Please calculate the height of a regular hexagonal pyramid with a base edge of 5cm and a wall height of w = 20cm. Please sketch a picture.
  5. Doug biked
    cyclist Doug biked 5 1/4 miles in 3/4 of an hour. What is his average speed?
  6. Christmas or Easter
    stromcek Please calculate this example by the Venn equation. They asked 73 students whether they like Christmas or Easter. 34 of them like one of the holidays. 39 loves Easter. There are twice as many students who wish both holidays than those who only love Ea
  7. Eq triangle minus arcs
    srafovana In an equilateral triangle with a 2cm side, the arcs of three circles are drawn from the centers at the vertices and radii 1cm. Calculate the content of the shaded part - a formation that makes up the difference between the triangle area and circular cuts
  8. Earnings per share
    usd The table below shows the stock price, earnings per share, and dividends per share for three companies for a recent year: Deere &Co. Price $65.70 earnings per share $4.40 Dividends per share $1.16 Google price $528.33 earnings per share $27.72 Dividends
  9. Intelligence test
    test Paľo, Jano, Karol, and Rišo were doing an intelligence test. Palo correctly answered half of the questions plus 7 questions, Jano to a third plus 18 questions, Karol to a quarter plus 21 questions and Risho to a fifth plus 25 questions. After the test, K
  10. Hexagon
    hexa_prism Calculate the surface of a regular hexagonal prism whose base edge a = 12cm and side edge b = 3 dm.
  11. Basketball team
    meter The heights of five starters on redwood high’s basketball team are 5’11”, 6’3”, 6’6”, 6’2” and 6’. The average of height of these players is?
  12. A loan
    exp_growth A loan in the amount of $944 is charged simple interest at an annual rate of 8.1%. How much money is owed 14 months after the loan was made?
  13. The parabolic segment
    ParabolicVolume The parabolic segment has a base a = 4 cm and a height v = 6 cm. Calculate the volume of the body that results from the rotation of this segment a) around its base b) around its axis.
  14. Bdf tablet
    bdf Detective Harry Thomson has come across a surprising mystery. As part of the weekend's action, the tablet he looked for dropped by 30%. He also recommended this bargain to his friend. However, it came to the shop on Monday, and the tablet was 30% more expe
  15. Ball bearings
    normal_d One bearing is selected from the shipment of ball bearings. It is known from previous deliveries that the inner bearing radius can be considered as a normal distribution of N (µ = 0.400, σ2 = 25.10^−6). Calculate the probability that the selected radius w
  16. The wellbore
    water The wellbore has a tributary of 2 m3 per hour. When there is no tapping, there are a stable 28 liters of water in the well. The pump suction basket is at the bottom of the well. At 14.00, the water was pumped out at a rate of 0.5 liters of water every se
  17. Picture frames
    picture_frame Destiny has to make 24 picture frames. Each frame uses 16 3/8 wood trim. 2/3 were completed on the first day. How many inches of wood trim is needed to complete the remaining frames on the second day?
  18. Two cylinders
    sudy Two cylinders are there one with oil and one with an empty oil cylinder has no fixed value assume infinitely. We are pumping out the oil into an empty cylinder having radius =1 cm height=3 cm rate of pumping oil is 9 cubic centimeters per sec and we are p
  19. Two integers
    x-5-x-3-graph Two integers, a and b, have a product of 36. What is the least possible sum of a and b?
  20. A number 2
    expr A number decreased by the difference between four and the number

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