# Algebra - problems - page 23

Number 839 divide into the two addends that the first was 17 greater than 60% of the second. Determine these addends.
2. Half life
Determine the half life of bismuth, when bismuth weight from the original weight of 32 g was only 2 grams in 242 minutes.
3. 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)?
4. Warehouse cars
From the warehouse started truck at speed 40km/h. After 1hour 30mins started from the same place same direction a car at speed 70 km/h. For how long and at what distance from the warehouse overtake a truck?
5. Exam average
Average of marks that have on the certificates students of 8.A class in mathematics is exactly 2.45. If we did not add 1 and 3 of sutdents Michael and Alena, who arrived a month ago, it would average exactly 2.5. Determine how many students have class 8.
6. Spirit
From 55% and 80% spirit we would like to produce 0.2 kg of 60% spirit. How many of them we must use in a solution?
7. Mom and daughter
Mom is 30 years older than the daughter. What is the age difference between them in 35 years?
8. Suit
The suit cost 119 euros. How much cost the pants if it is 50% cheaper than the jacket.
9. Volatile percents
Kent is working as a forex trader. Suffered a loss of 65.8 percent. Calculate what percentage must now earn to lift from loss?
10. Cubes
Carol with cut bar 12 cm x 12 cm x 135 cm to the cubes. Find the sum of all the surfaces of the resulting cubes.
11. Cone container
Rotary cone-shaped container has a volume 1000 cubic cm and a height 12 cm. Calculate how much metal we need for making this package.
12. Sprayers
The vineyard can be sprayed first sprayer in 5 hours and with the second in 8 hours. How long would it take if we use sprayers both at once?
13. Work
First paver pave pavement for 27 hours. Second for 27 hours. Started first paver and after 4 hours, join the second. How long will they finish pavement?
14. Bath
In the bath is 30 liters of hot water. Then added 36 liters of cold water at temperature of 19 °C decreased temperature of water to 41 °C. What was the initial temperature of the hot water?
15. 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.
16. Bronze, tin and copper
Bronze is an alloy of tin and copper. An alloy of 10% tin and 90% copper is Gunmetal. If it contains 20% tin and 80% copper, it is bell metal. How many tons of molten bell metal and how many tons of copper is needed to make 100 tons of Gunmetal?
17. Jan
Jan is 13 years and Peter 21 years old. For how many years will their ages in the ratio of 7:9?
18. Paul and Honza
Honza went to chat on a bike without a break 4.0 hours. Paul the same way without breaks 50 minutes longer. The difference between the speeds of the two boys was the one kilometer per hour. How fast was Paul, if you know that the speed of the boys did not.
The voltage station is every day changing the master password, which consists of three letters. Code generation process does not change and is based on the following procedure: The following letters (A) to (I) correspond to different numbers from 1 to 9. I
20. Airplane
Aviator sees part of the earth's surface with an area of 200,000 square kilometers. How high he flies?

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