# Reason - examples - page 5

1. Team
The football team has 11 players. Their average age is 20 years. During the match due to injury, one player withdraws and the average age of the team is 18. How old was injured player?
2. Chocolate
How many times should be broken chocolate consisting of 10 × 12 pieces to get the 120 parts?
3. Chocholate
Table of chocolate is divided into squares on its surface. Lengthwise has 15 squares and widthwise 19 squares. We must chocolate broke into individual squares. How many times we have broke it to get only individual squares? It is not permitted to break
4. Phone numbers
How many 7-digit telephone numbers can be compiled from the digits 0,1,2,..,8,9 that no digit is repeated?
5. Octahedron - sum
On each wall of a regular octahedron is written one of the numbers 1, 2, 3, 4, 5, 6, 7 and 8, wherein on different sides are different numbers. For each wall John make the sum of the numbers written of three adjacent walls. Thus got eight sums, which also.
6. Rabbits
In the hutch are 48 mottled rabbits. Brown are 23 less than mottled and white are 8-times less than mottled. How many rabbits are in the hutch?
7. Pumps
The tank is filled with two pumps in 16 minutes. The first pump is filled in 30 minutes earlier than two one. How many minutes is filled with the first pump?
8. Homework
The monthly fee for the phone is 12 USD and for phone unit 0.08 USD. How much family pay phone in the first quarter Q1, if on January 1 had on the counter 97362 units and on April 1 97946 units.
9. Compound interest
Calculate time when deposit in the bank with interest 2.5% p.a. doubles.
10. n-gon
Gabo draw n-gon, which angles are consecutive members of an arithmetic sequence. The smallest angle is 70° biggest 170°. How many sides have Gabo's n-gon?
11. Pension or fraud
Imagine that your entire working life working honestly and pay taxes and to Social Insurance (in Slovakia). You have a gross wage 730 Euros, you pay social insurance (you and your employer) monthly € 263 during 44 years and your retirement is 354 Eur.
12. Report card
Ivor hit 5× grade 5 at the beginning of the school year. How many times must now catch grade 1 to get grade 2 on report card?
13. Dice
How many times must throw the dice, the probability of throwing at least one six was greater than 90%?
14. 2x cone
Circular cone height 76 cm was cut plane parallel with base. Volume of these two small cones is the same. Calculate the height of the smaller cone.
15. Clock
What time is now, if the time elapsed after noon is 2/10 of time that elapses before midnight?
16. Solidarity
Imagine a word solidarity means that salt donation to the needy, who have neither the salt. If we take word solidarity has word base salt + gift (only in Slovakian language). Calculate how many kilos of salt sympathetic citizen "gives" government a year i
17. Sequence
In the arithmetic sequence is a1=-1, d=4. Which member is equal to the number 203?
18. Stock market
Simon one day decided to invest € 62000 to the stock market. After six months he invested July 25 stock markets fell by 47%. Fortunately for Simon from July 25 5 to October 25 his shares have risen by 39%. Simon is then: ?
19. Tea blend
Tea blends are maked from two kinds of tea. In standard tea mixture are two teas in the ratio 1:3 and 40 g costs 42 CZK. In the premium tea mixture are weighing two teas in the ratio 1:1 and 50 grams costs 60 CZK. How much cost 10 grams of more expensive k
20. Discounts on rail (ZSSK)
The railway company ZSSK offers a discount of 15% (REGIONAL) for 5 Eur/year. Calculate the real discount rate as a percentage, where passengers will travel 19 Eur per week.

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