# Grade - examples - page 189

1. Barrels
Peter has 42 barrels. One-sixth of them are filled with lemonade, one third is filled with wine and half is empty. Calculate how many barrels are with each filling.
2. Inscribed
Cube is inscribed in the cube. Determine its volume if the edge of the cube is 10 cm long.
3. Pupils
There are 32 pupils in the classroom, and girls are two-thirds more than boys. a) How many percents are more girls than boys? Round the result to a whole percentage. b) How many are boys in the class? c) Find the ratio of boys and girls in the class. Wr
4. Two buses
The first bus runs 15 minutes the second bus runs after 21 minutes. Together they both leave at 7:00 on Monday. When and what day will they meet?
5. Granules
Katy had two dogs. The first one ate a pack of granules a week and the other two times longer. Katka bought them two bags of granules. How long does it last for both dogs?
6. Cube diagonals
Calculate the length of the side and the diagonals of the cube with a volume of 27 cm3.
7. Bulbs
There are 875 identical light bulbs in the sports hall lightning for 2 hours. How long does it lightning 100 this light bulbs?
8. Iron ball
The iron ball has a weight of 100 kilograms. Calculate the volume, radius, and surface if the iron's density is h = 7.6g/cm3.
9. Prism 4 sides
Find the surface area and volume four-sided prism high 10cm if its base is a rectangle measuring 8 cm and 1.2dm
10. Functions f,g
Find g(1) if g(x) = 3x - x2 Find f(5) if f(x) = x + 1/2
11. Pravoúhly trojúhelník
Určete obsah pravoúhlého trojúhelníku, jehož délky stran tvoří po sobě jdoucí členy aritmetické posloupnosti a poloměr kružnice opsané tomuto trojúhelníku je 5 cm.
12. Products
15 products are 48 € more expensive than 12 products. How many euros will it cost five same products?
13. The factory
The factory z can complete an order in 12 days, factory p in 18 days. For how many days does an order completed when the first two days work only the factory z and then both factories?
14. Mixture
How many percentages mixtures do we get by adding 23ml of matter to 89ml of water?
15. Triplets
Three years ago, the triplets Pavel, Petr, and Luke and their five-year-old sister Jane had together 25 years. How old is Jane today?
16. Perpendicular prism
Calculate the volume of the perpendicular prism if its height is 60.8 cm and the base is a rectangular triangle with 40.4 cm and 43 cm legs.
17. Composite ratio
Jakub, Aneta, and Lenka divided 1342 USD in the ratio 5/2: 3/10: 1/4. How much did Lenka take?
18. On the trip
On the trip were more than 55 children, but less than 65 children. Groups of 7 could be formed, but groups of 8 no. How many children were on a trip?
19. Population growth
How many people will be on Earth from two people for 5,000 years, if every couple has always 4 children, (2 boys and 2 girls) at the age of 25-35, and every man will live 75 years?
20. Water tank
In an empty fire tank, 2150 hl of water jetted in 5 hours. How many hectoliters of water was jetted every hour? How many hectoliters of water was in the tank after three hours?

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