Examples for 8th grade - page 77

  1. Flowerbed
    tulipany Family cultivated tulips on a square flower bed of 6 meters. Later they added the square terrace with a side of 7 meters to their house. One vertex of the terrace lay exactly in the middle of a tulip bed, and one side of the terrace divided the side of the
  2. Log
    5962705_ad Worker cut his thick log to 6 pieces for 30 min. How long he cut log to 12 pieces?
  3. Addends
    two Number 118 divide into two addends, so first addend is 69 greater than 75% of the second addend.
  4. Theatro
    divadlo_1 Theatrical performance was attended by 480 spectators. Women were in the audience 40 more than men and children 60 less than half of adult spectators. How many men, women and children attended a theater performance?
  5. Potatoes
    zemiaky_3 Daniela and Michael would jointly dug potatoes for 7.5 hours. But if Daniela was working alone she would take 2.5 hours more as if he were working with Michael. Determine how much for the work done by Michael himself and how much Daniela herself.
  6. Megapascals
    engine What is the area of crosssection of the piston, if the force of 300 kN produces a pressure of 5 MPa?
  7. Z7-I-4 stars 4949
    hviezdicky_mo Write instead of stars digits so the next write of product of the two numbers to be valid: ∗ ∗ ∗ · ∗ ∗ ∗ ∗ ∗ ∗ ∗ 4 9 4 9 ∗ ∗ ∗ ∗ ∗ ∗ 4 ∗ ∗
  8. Assistant
    psaci-stroj Assistant rewrote 15% of the entire manuscript in 12 hours. How many hours must still write to rewrite the rest of the manuscript?
  9. Trams
    tramvaje Two trams started at the same time from the same place. One tram journey takes 30 minutes and the second 45 minutes to its final stop. How long will trams meet again?
  10. Pool
    bazen-2-05_1 The pool has the shape of a cylinder with a diameter 4.6m, the presumed height is 130cm. The bucket fits 12l of water. How many buckets do you have to bring to fill this pool?
  11. Base, percents, value
    percent_1 Base is 344084 which is 100 %. How many percent is 384177?
  12. Book read
    books_12 If Petra read 10 pages per day, she would read the book two days earlier than she read 6 pages a day. How many pages does a book have?
  13. Pumps
    pumps Five pumps pumped 1,800 hl of water for 3 hours. How many hectoliters of water pump same two powerful pumps for six hours?
  14. Plum
    plumbs_1 On the platter are plum. How many were there if its have to be able to share equally among 8,10 and 12 children?
  15. Three figures - numbers
    numbers34 The sum of three numbers, if each is 10% larger than the previous one, is 662. Determine the figures.
  16. Class 9A
    boy On the final certificate have one quarter of the class 9A mark "C" of mathematics, seventh mark "C" from the Czech language and two students failed in chemistry. How many students attend class 9A?
  17. Greenhouse
    foliovnik Garden plastic greenhouse is shaped half cylinder with a diameter of 6 m and base length 20 m. At least how many m2 of plastic is need to its cover?
  18. Line segment
    lines_5 Cut a line segment of 15 cm into two line segments so that their lengths are in ratio 2:1. What length will each have?
  19. Candy
    bonbons_5 The price for 1kg of more expensive candy is 125 CZK. The price for 1kg of cheaper candy is 100 CZK. We make two different blends of candy. And now. The second blend contains 2kg of more expensive candy and several kg of cheaper candy. The price per 1 kg o
  20. Sale off 2
    sale A pair of of blues jeans went on sale. After a 30% reduction the pants cost $35. How much did the jeans cost before the price reduction?

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