# Reason - examples - page 10

1. Three digits number
How many are three-digit integers such that in they no digit repeats?
2. Temperature calculus
Calculate percentage of temperature increase if changed from -9°C to 22°C?
3. David number
Jana and David train the addition of the decimal numbers so that each of them will write a single number and these two numbers then add up. The last example was 11.11. David's number had the same number of digits before the decimal point, the Jane's number
4. Trickster
Figliarko has 13 cents less than Hana. Together they have 57 cents. How many cents has Hana and how many Figliarko?
5. Tablecloth
I embroider tablecloth in 20 days but if I embroider 3/4 hours a day I have embroider it for 15 days. How long do I embroider a day?
6. Cross-country competition
Cross-country competition was attended by 76% of pupils of class 9.B. Class consis of 16 boys, two of whom did not run and 4 girls did not run. How many girls go to class 9.B?
7. Combi-triangle
On each side of the square is marked 10 different points outside the vertices of the square. How many triangles can be constructed from this set of points, where each vertex of the triangle lie on the other side of the square?
8. Number train
The numbers 1,2,3,4,5,6,7,8 and 9 traveled by train. The train had three cars and each was carrying just three numbers. No. 1 rode in the first carriage, and in the last carriage was all odd numbers. The conductor calculated sum of the numbers in the first
9. Classroom 3
How many children are in the classroom, where 13 children are higher than Lenka and 9 children lower than Lenka?
10. Coin
How many 50-cent coins must be put in a row that next 50-cent coins after them (above) rolled on it axis?
11. Forest ranger
Forest ranger watching from the hide deers. At one time point he can see 6 deers. How many maximum deers can be see by 3 rangers at same time?
12. Divers
20-member group of divers carries the air for 15 hours of diving. 4 members of the expedition sick or wasn't came. How many hours is sufficient air to other divers?
13. Chicken
I threw three chicken for a handful of grains and I noticed that it eat in a ratio of 8:7:6 and two of them grabbed 156 grains. How many grains have fought that chicken?
14. Unions
Calculate how much money per year would go to the treasury of unions if 218 thousand employee join unions with an average net salary of 407 euros and if memberhip in union cost 1% of the net monthly salary.
15. Four-digit number
Find also a four-digit number, which quadrupled written backwards is the same number.
16. Workman - shift
The worker produces 300 components per shift. How many components would be produced in 18 shift, if his performance gradually increased every shift by 3 components?
17. The body
The body on the figure consists of cubes with an edge length 10 cm. What surface has this body?
18. Tunnels
Mice had built an underground house consisting of chambers and tunnels: • each tunnel leading from the chamber to the chamber (none is blind) • from each chamber lead just three tunnels into three distinct chambers, • from each chamber mice can get to any
19. Mother and daughter
Three years ago mother was three times older than daughter. After nine years she will be only twice old. How old is mother (and daughter)?
20. Grandfather
The grandfather is three years older than an grandmother. The average age of the grandmother, the grandfather and their seven grandchildren is 28 years. The grandchildren have a total of 105 years. Calculate how old is grandfather.

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