Examples for 8th grade - page 34

  1. Bricks wall
    tehly_1 There are 5000 bricks. How high wall thickness of 20 cm around the area which has dimensions 20 m and 15 m can use these bricks to build? Brick dimensions are 30 cm, 20 cm and 10 cm.
  2. TV diagonal
    diagonal Diagonal TV is 0.56 m long, how big the television sreen is if the aspect ratio is 16:9?
  3. Sales off
    sweater If a sweater sells for $ 12 after a 25% markdown, what was its original price?
  4. Bronze, tin and copper
    zvon Bronze is an alloy of tin and copper. An alloy of 10% tin and 90% copper is Gunmetal. If it contains 20% tin and 80% copper, it is bell metal. How many tons of molten bell metal and how many tons of copper is needed to make 100 tons of Gunmetal?
  5. Scale
    valec_vykres Cylinder was drawn in scale 7:1. How many times is the volume of the cylinder smaller in reality?
  6. Lathe
    sustruh Calculate the percentage of waste if the cube with 52 cm long edge is lathed to cylinder with a maximum volume.
  7. Internal angles
    mo-klm The ABCD is an isosceles trapezoid, which holds: |AB| = 2 |BC| = 2 |CD| = 2 |DA|: On its side BC is a K point such that |BK| = 2 |KC|, on its side CD is the point L such that |CL| = 2 |LD|, and on its side DA the point M is such that | DM | = 2 |MA|. Dete
  8. Circle sector
    vysec Circular sector with a central angle 10 ° has area 254 cm2. Calculate its radius r.
  9. The camp
    diary At the end of the camp a 9 friends exchanged addresses. Any friend gave remaining 8 friends his card. How many addresses they exchanged?
  10. Addends
    1plus1 Number 389 divide into the two addends that the first was 6 greater than 60% of the second. Determine these addends.
  11. Homework - jumps
    castle_children Sasha jumped 142 cm Peter 4 cm more than Jirka. Jirka 6 cm less than Misha. Misha 7 cm less than Filip and Filip half as much Sasha and Petr together. How far each jumped?
  12. Solution
    chemistry In 300 dl red solution is 154 dl red color and in 132 dl blue solution is 12 dl blue color. How many dl of red and blue dl color solution must be mixed to get a mixture of 499 dl contain 168 dl of color?
  13. Arc
    angles Convert to arc measures (radians): 1367 ° Result write as a multiple of π
  14. Rectangular trapezoid
    rt_licho The rectangular trapezoid ABCD is: /AB/ = /BC/ = /AC/. The length of the median is 6 cm. Calculate the circumference and area of a trapezoid.
  15. Against each other
    Lotus_Esprit From two points A, B distant 45 km at the same time started two cars against each other at speeds 81 km/h and 67 km/h. How long does cars meet and what distance passes each of them?
  16. Baker
    pekar The baker makes from 10 kg of flour 12 kg dough. How much flour he need to make a 100 kg dough?
  17. Two cars
    car_racing Car A1 goes at average speed of 133 km/h and the second car A2 goes at 128 km/h. How many second will it take car A1 to circulate car A2? Assume that both cars are 4.7 meters long and the safety gap between cars is 2.7 meters.
  18. Logs
    tramy The log has diameter 30 cm. What's largest beam with a rectangular cross-section can carve from it?
  19. Summerjob
    pat_mat Albert, Beny, Cyril and Dan worked on summerjob. From the total revenue Albert received 2/5, Beny 1/6 , 3/10 Cyril and Dan the rest which is 324 euros. How many euros earned every one of them?
  20. Railways - golden parachutes
    pavel-kravec_kdh As often happens in Slovakia habit, the state's financial institution which takes from poverty and gorilas give. A hardworking punishing taxes. Let's look at a short work of director Railway Company ZSSK - Mgr . P. K. : 18 months 'work' as director r

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