# Grade - examples - page 137

1. Cards
From a set of 32 cards we randomly pull out three cards. What is the probability that it will be seven king and ace?
2. Line segment
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?
3. Pool
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?
4. Hexagonal prism 2
The regular hexagonal prism has a surface of 140 cm2 and height of 5 cm. Calculate its volume.
5. Contestants
In the competition it was possible to get 0-5 points. In fact, 5 contestants of the 15 best contestants has earned 5 points or 4 points (which have won 10 contestants). The number of contestants who earned 3 points was the same as the number of contestan
6. Disco
On the disco goes 12 boys and 15 girls. In how many ways can we select four dancing couples?
Mam used 9 red, 9 green apples and 3 pears to prepare juice. How many pieces of fruit used by mom to prepare this juice?
8. Water level
To cuoid shaped poll, bottom size 2m and 3.5m; flows water at a rate of 50 liters per minute. How long will take to water reach level 50 cm?
9. Three figures - numbers
The sum of three numbers, if each is 10% larger than the previous one, is 662. Determine the figures.
10. Gas consumption
The vessel consume 100 tons of gas in 250 miles. How many fuel will the vessel consume if it travels 400 miles?
11. Sick
Sick Marcel already taken six tablets, which was a quarter of the total number of pills in the pack. How many pills were in the pack?
12. Regular octagon
Draw the regular octagon ABCDEFGH inscribed with the circle k (S; r = 2.5 cm). Select point S' so that |SS'| = 4.5 cm. Draw S (S '): ABCDEFGH - A'B'C'D'E'F'G'H'.
13. Greenhouse
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?
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?
15. Number
I think the number. If I add to its third seven I get same as when to its quarter add 8. Which is the number?
Fill letters instead of digits so the indicated sum (equal letters represent equal digits). What number is hidden under the letter J? A A H A H O A H O J -------------------------- 4 3 2 1
17. Saving per cents
The first day I save 1 cent and every next day cent more. How many I saved per year (365 days)?
18. Candy
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
19. Kilo candy
One kilogram of chocolate candy cost 10 euros. Kate buys 250 grams and had the 8 pack of candy. How much does cost one bonbon?
20. Quotient 3
If the quotient of 8/13 and 2 is subtracted from the product of 1 3/4 and 8/21, what is the difference?

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