Examples for 8th grade - page 14

  1. TVs
    tv Production of television sets increased from 3,500 units to 4,200 units. Calculate the percentage of production increase.
  2. Digging companies
    companies Company A would dig a pit for 12 days, company B for 15 days, company C for 20 days and the company D for 24 days. Work began together companies C and D, but after three days joined them other two companies. How long took to dig a pit?
  3. Oil rig
    oil_rig_tower Oil drilling rig is 23 meters height and fix the ropes which ends are 8 meters away from the foot of the tower. How long are these ropes?
  4. Prism
    prism-square The lenght, width and height of a right prism are 18, 14 and 9 respectively. What is the lenght of the longest segment whose endpoints are vertices of the prism?
  5. Compass
    wind_rose What angle are between directions W (West) and SE (SouthEast) on the compass?
  6. Tippler
    flaska_mlieka Bottle with cork cost 9.9 Eur. The bottle is 0.9 euros more expensive than cork. How much is a bottle and the cork?
  7. Five girls
    cats_cicky Five girls traveling by bus. Each holds in each hand two baskets. In each basket are four cats. Each cat has three kittens. Two girls exits bus. How many legs are in the bus?
  8. Components
    components In the box are 6 white, 4 blue and 2 red components. What is the probability that we pull one white, one blue and one red component without returning?
  9. Sea water
    sea Mixing 68 kg of sea water with 73 kg rainwater is created water containing 3% salt. How many percent sea water contains salt?
  10. Mortgage
    hypo_real_estate Family XY wants to take the bank mortgage (loan for an apartment/house) in the amount of € 100,000. Bank for processing the mortgage charges a fee of 0.79% of the amount borrowed. How many euros is this fee?
  11. Simply equation
    img_reci Solve this equation for x: ?
  12. Workman - shift
    favorit_skoda The worker produces 300 components per shift. How many components would be produced in 18 shift, if his performance gradually increased every shift by 3 components?
  13. Discount
    sales_discount Product has been discounted twice by 14%. What is the total discount given?
  14. Expansion
    magnification If one side of the rectangle is larger 3-times and second 4-times, what percentage increases the area of rectangle?
  15. Cylinder - A&V
    cylinder The cylinder has a volume 253. The base has a radius 5. What is the area of surface of the cylinder?
  16. 4 pipes
    roury The tank flows out by 4 pipes in 6 hours 120 hl water. How much water flows out of 5 pipes of the same diameter in 14 hours?
  17. Revenue
    odmena Mr. Robert and Mr. Norbert get together € 1400. The revenue split in the ratio of 4:3, depending upon each work. How many got each of them?
  18. Pillar
    sliced_pyramid Calculate volume of pillar shape of a regular tetrahedral truncated pyramid, if his square have sides a = 13, b = 21 and height is h = 33.
  19. Wire
    cu_wire One pull of wire is reduced its diameter by 9%. What will be diameter of wire with diameter 9 mm over 8 pulls?
  20. Acid
    acid_1 The barrel is 239 litres of 31% acid. How many percent acid occurs when 88 litres revoke and replace it with the same amount of water?

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