# Grade - examples - page 192

1. Highway tunnel
The highway tunnel was built from two ends in the north-south direction. The average daily performance of the "northern party" rasters was higher than the average daily power of the "southern party" of the rasters. After 55 business days, both parties met.
2. Each chair
Each chair costs twice less than two tables. One table costs 720 Czech crowns. How many crowns are the table and 4 chairs?
3. Highway repair
The highway repair was planned for 15 days. However, it was reduced by 30%. How many days did the repair of the highway last?
4. Father 7
Father is 6 times older than his son. After 4 years, the father will only be 4 times older. What are their present ages?
5. Three workplaces
How many ways can we divide nine workers into three workplaces if they need four workers in the first workplace, 3 in the second workplace and 2 in the third?
6. Edges or sides
Calculate the cube volume, if the sum of the lengths of all sides is 276 cm.
7. Acid evaporation
How many kilograms of water do we have to evaporate from 100 kg of 32% acid to make it 80% concentration?
8. Hugo has
Hugo has 12 apples, Julka has seven more than Hugo and six less than Anna. How many apples have Anna and how many Julka?
9. Classmates
Roman is ranked 12th highest and eleventh lowest pupil. How many classmates does Roman have?
10. Cylinder-shaped vase
If the cylinder-shaped vase is filled with water up to 35 cm, it contains 1 liter of water. How much water will it contain if it is filled to a height of 45cm?
11. Three 43
Three brothers inherited a cash amount of 62,000 and they divided it among themselves in the ratio of 5:4:1. How much more is the largest share than the smallest share?
12. Diagonals of the rhombus
How long are the diagonals e, f in the diamond, if its side is 5 cm long and its area is 20 cm2?
13. Running
Joanne ran 8 1/2 Kyleigh 1 2/3 and John 6 3/4 miles in one day. How many miles did the girls run in 3 days?
14. Sweater
Dana confuses sweater and wool has a choice of seven colors. In how many ways she can choose from three colors to the sleeves?
15. Michal
Michal has 2.90 per hour. How much does he earn during the week of the summer job?
16. Water reservoir
One drain hole emptied the water from the tank for 20 hours, with the second drain for 30 hours. How long will the water drain from this tank if we open two drains simultaneously?
17. The pot
The pot is a cylinder with a volume of V = 7l and an inner diameter of d = 20cm. Find its depth.
18. Value
Find the value of the expression: 6!·10^-3
19. Median and modus
Radka made 50 throws with a dice. The table saw fit individual dice's wall frequency: Wall Number: 1 2 3 4 5 6 frequency: 8 7 5 11 6 13 Calculate the modus and median of the wall numbers that Radka fell.
20. The big clock
The big clock hands stopped at a random moment. What is the probability that: a) a small hand showed the time between 1:00 and 3:00? b) the big hand was in the same area as a small hand in the role of a)? c) did the hours just show the time between 21:00.

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