Examples for 8th grade - page 74

  1. Cuboid and ratio
    kvader Cuboid has dimensions in ratio 1:2:6 and the surface area of the cuboid is 1000 dm2. Calculate the volume of the cuboid.
  2. Motel
    motorest Three different dinners A, B, C are served in the motel. Three 20 members went to motel. Group 1 ordered dinners: A 20 members and their average dinner price in the group was CZK 200. From Group 2, they ordered a A: 10 persons, B 10 dinners, and their aver
  3. Base, percents, value
    percent_1 Base is 344084 which is 100 %. How many percent is 384177?
  4. Pet store
    fish In a pet store, they are selling out the fish from one aquarium. Ondra wanted half of all fish, but they don't wish cut by hal fany fish he got one more than demanded. Matthew wished the remaining half of the fish, but as Andrew got half the fish more th
  5. Blueberries 2
    boruvky_2 Lenka and Martin collected eight liters of blueberries in two hours. How long will take to collect blueberries by Lenka itself, if we know that she collect all 2.5 hours less than Martin?
  6. Right triangle ABC
    right_triangle_2 Calculate the perimeter and area of a right triangle ABC, if you know the length of legs 4 cm 5.5 cm and 6.8 cm is hypotenuse.
  7. Disc
    vysek.JPG Circumference of the disk is 78.5 cm. What is the circumference of the circular arc of 32° on the disc?
  8. Circumscribed circle to square
    kruznice Find the length of a circle circumscribing a square of side 10 cm. Compare it to the perimeter of this square.
  9. Common cylinder
    valec_2 I've quite common example of a rotary cylinder. Known: S1 = 1 m2, r = 0.1 m Calculate : v =? V =? You can verify the results?
  10. Six years
    children_9 In six years Jan will be twice as old as he was six years ago. How old is he?
  11. Glass
    sklenice_1 Trader ordered from the manufacturer 200 cut glass. The manufacturer confirmed the order that the glass in boxes sent a kit containing either four or six glasses. Total sent 41 boxes. a) How many boxes will contain only 4 glasses? b) How many boxes will co
  12. Tickets
    stadion_1 On the football tournament ticket cost 45 Kc for standing and 120kč for sitting. Sitting spectators was 1/3 more than standing. The organizers collected a total 12 300 Kc. How many seated and standing seats (spectators)?
  13. Sales off 2
    lcd_1 Computer monitor sold for 8400 CZK in March. In April, dealer price decreased by 798 CZK. Calculate the percentage by which the price was reduced.
  14. Sales of products
    cukriky_9 For 80 pieces of two quality products a total sales is 175 Eur. If the first quality product was sold for n EUR per piece (n natural number) and the second quality product after 2 EUR per piece. How many pieces of the first quality were sold?
  15. Lawns
    grass Before a sports hall are two equally large rectangular lawns, each measuring 40 m and 12 m. Maintenance of 10m² lawn cost 45 CZK yearly. On each lawn is circular flowerbed with a diameter 8 meters. How much money is needed each year to take on lawn care?.
  16. Rectangle 3-4-5
    diagonal_rectangle_1 The sides of the rectangle are in a ratio of 3:4. The length of the rectangle diagonal is 20 cm. Calculate the content of the rectangle.
  17. 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?
  18. Unknown number
    nums Identify unknown number which 1/5 is 40 greater than one tenth of that number.
  19. Megapascals
    engine What is the area of crosssection of the piston, if the force of 300 kN produces a pressure of 5 MPa?
  20. Pharmacy
    roztoky_3 The pharmacy add to 3 liters of 95-percent alcohol 5 liters of 38.04 percent alcohol. How many percent pharmacy got?

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