Examples for 8th grade - page 61

  1. Lift
    lanovka_2 The largest angle at which the lift rises is 16°31'. Give climb angle in permille.
  2. Driving school
    bmw-autoskola Driving final exam involving 10 attendants. The exam consists of three parts. 2 fails at test (quiz) and 6 students fails on car skills test on playground (slalom between the cone). The practical part of the test - driving in town in the real traffic - al
  3. Percentages
    percent2 Expressed as a percentage:
  4. Candies
    bonbons_10 There are two types of candies in the store at 20 CZK/kg and 80 CZK/kg. How much will be cost a mix if we mix 22kg cheaper and 4kg more expensive candies?
  5. Isosceles trapezoid
    lichobeznik_5 Calculate the content of an isosceles trapezoid whose bases are at ratio 5:3, the arm is 6cm long and it is 4cm high.
  6. Tmp workers
    profesiadays Three temporary workers cleaned 60 m of walkway in 5 hours. How many meters of the walkway cleared seven volunteers for eight hours?
  7. Sisters
    sestry20091 Sisters Janka and Danka are saved together 220 CZK. On a trip to Janka wants to take a fifth of her savings and Danka quarter. Then they will have 50 CZK on the trip. How much money saved Janka and Danka?
  8. Proof I
    ithinkiam When added to the product of two consecutive integers larger one, we get square larger one. Is this true or not?
  9. Trapezium
    lichobeznik_3 The length of the base and the height size of the base of the trapezium is at ratio 5:3:2, the content area of the trapezium is 128 cm2. Calculate the length of the base and the height of the trapezoid.
  10. Grass garden
    koseni Mr. Grass would itself be mowed garden for 5 hours. His son Michael could do it for 7 hours. They agreed that they wake up at 5 am and begins to mow together. Ms. Grass needs drive into town at 8.30. Michael says that at that time they're done with work..
  11. Repairman
    makak Repairman has vowed to do repair work at the plant for 25 days. However work had to be shortened, and therefore he took helper worker. Together they made all the corrections for the whole days. How long it would take work to helper worker?
  12. 3 years
    ekonomicky-rast The company has increased the number of employees. In year 2005 compared to 2004 13% more, in 2006 18% more against the previous year, in year 2007 20% more compared to 2006. How many % increase in the number of employees in 3 years?
  13. Surface area 2
    cubes Calculate how many % reduce the surface area of the cube is we reduced length of each edge by 10%.
  14. Isosceles trapezoid
    lichobeznik_6 In an isosceles trapezoid KLMN intersection of the diagonals is marked by the letter S. Calculate the area of trapezoid if /KS/: /SM/ = 2:1 and a triangle KSN is 14 cm2.
  15. Cube volume
    cube6 The cube has a surface of 384 cm2. Calculate its volume.
  16. Ethnicity
    indian Share of ethnicity XY is 26%, which is 1/9 more than in the prewar period. What was the share of that ethnicity in the pre-war period?
  17. Force meter
    archimedes We put the statuette on the force meter. The force meter showed a value 25 N. Then we placed the statuette on the force meter completely immersed in the water. The force meter showed a value 17 N. What is the volume of the statuette?
  18. The chord
    circles_4 Calculate a chord length which the distance from the center of the circle (S, 6 cm) equals 3 cm.
  19. Pupils at cinema
    tickets_1 Alena bought movie tickets for two groups of pupils. The first group purchased 7 tickets for 1st and 5 tickets for 2nd place and she pay 62Kč. For the second group bought 11 tickets for 1st and 4 tickets for 2nd place and pay 82Kč. How much was the ticket
  20. Tripled square
    squares4_1 If you tripled the length of the sides of the square ABCD you increases its content by 200 cm2. How long is the side of the square ABCD?

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