New math problems - page 3

  1. Unknown number 23
    cisla_4 Find 2/3 of unknown number, which is two thirds of the 99.
  2. Trapezoid
    lichob_2_1 How long are the trapezoid bases with area 24 cm2 and height 3 cm. One base is 3 times longer than the shorter.
  3. Megapascals
    engine What is the area of crosssection of the piston, if the force of 300 kN produces a pressure of 5 MPa?
  4. Rope
    navijak How many meters of rope 10 mm thick will fit on the bobbin diameter of 200 mm and length 350 mm (central mandrel have a diameter 50 mm)?
  5. V-belt
    remenice-a-remen1 Calculate a length of the V-belt when the diameter of the pulleys is: D1 = 600 mm D2 = 120 mm d = 480 mm
  6. Savings
    penize_29 Paul has a by half greater savings than half Stanley, but the same savings as Radek. Staney save 120 CZK less than Radek. What savings have 3 boys together?
  7. Center of gravity
    triangles_9 In the isosceles triangle ABC is the ratio of the lengths of AB and the height to AB 10:12. The arm has a length of 26 cm. If the center of gravity T of triangle ABC find area of triangle ABT.
  8. Ounce
    energy_1 749 calories in a 7 - ounce serving . What is the unit rate?
  9. Cards
    cards_8 From a set of 32 cards we randomly pull out three cards. What is the probability that it will be seven king and ace?
  10. Bicycles
    cyclist_11 You're the owner of the transport 's learning playground. Buy bicycles of two colors but you've got to spend accurately 120000 Kč. Blue bike costs 3600Kč and red bicycle 3200Kč.
  11. Basic form
    time_3 Expressed the ratios of values in the basic form: 0,5 t : 1,2 kg 200 l : 0,15 m3 12 t : 3600 kg 500 kg : 2,5 t 0,9 kg : 500 g 3,6 m : 240 cm 1200 mm : 2,4 m 300 l : 0,3 m3 6 min 30 s : 900 s
  12. Family
    family_14 Mom is 42 years old and her daughters 13 and 19. After how many years will mother as old as her daughter together?
  13. Tree shadow
    tree3 The shadow of the tree is 16 meters long. Shadow of two meters high tourist sign beside standing is 3.2 meters long. What height has tree (in meters)?
  14. Kangaroo
    klokan_1 Kangaroo do 10 jumps in 1 minute and then three minutes lie , then will make 10 jumps in 1 minute and 3 minutes lie, and so on. Find the shortest time in which kangaroo do 30 jumps.
  15. Sun rays
    sfinga-a-cheopsova-pyramida-w-4066 If the sun's rays are at an angle 60° then famous Great Pyramid of Egypt (which is now high 137.3 meters) has 79.3 m long shadow. Calculate current height of neighboring chefren pyramid whose shadow is measured at the same time 78.8 m and the current hei
  16. Trapezoid MO-5-Z8
    lichobeznik-stredni_pricka_2 Trapezoid KLMN has bases 12 and 4 cm long. The area of triangle KMN is 9 cm2. What is the area of the trapezoid KLMN?
  17. Percentages 5
    usd_1 $5.25 is 7 1/2% of what number?
  18. Railway wagon
    cargo The railway wagon holds 75 m3 load. Wagon can carry a maximum weight of 30 tonnes. What is the maximum density that may have material with which we could fill this whole wagon? b) what amount of peat (density 350 kg/m3) can carry 15 wagons?
  19. Quadratic inequation
    eq2_8 If 5x + x² > 100, then x is not
  20. Cube in sphere
    sphere4 The sphere is inscribed cube with edge 8 cm. Find the radius of the sphere.

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