# Themes, topics - math word problems

1. Apples 2 Dried apples contain 15% water. Fresh apples contain 80% water. How many kg of apples we need buy in order to get 3 kg of dried apples?
2. Alcohol mixture From 55% and 80% alcohol we have to produce 0.2 kg of 60% alcohol. How many of them do we use in solution?
3. Banknotes \$ 1390 was collected. How much was in \$20 notes and how many in \$50 notes in that order? How many solutions exists?
4. Cyclist vs car Cyclist rode out of the city at 18 km/h. 1 hour 30 minutes behind him started car and caught up with the cyclist in 50 minutes. How fast was driving the car? Where (what kilometer) from the city car overtook a cyclist?
5. The swing To swing the two girls. Aneta weight 45 kg and Simon 35 kg weight. How far should sit Simon from the middle of swing so it is balanced, if we know that Aneta is sitting at distance 1,5m? How far are girls sitting apart?
6. Candy - MO Gretel deploys to the vertex of a regular octagon different numbers from one to eight candy. Peter can then choose which three piles of candy give Gretel others retain. The only requirement is that the three piles lie at the vertices of an isosceles triang
7. Runner 2 Marian run 12 meters in 8 seconds. How far would Marian run for 70 seconds, if still run at the same pace?
8. Truck and car At 6h45min the truck started at a speed of 36 km/h. At 7h30m behind it a passenger car. Find the average speed of passenger car if it will catch truck 72 km away from the factory.
9. Sawmill factory Peter works in the factory. The bus stop is 10 km from the factory. Therefore, always when the bus arrives for Peter, the driver leaves factory and takes him to work. They are coming at the saw exactly at 8:00. Today the bus arrived 11 minutes earlier and.
10. Workers Group of workers washing half of the windows of the building in two hours. How long will take half the workers wash all the windows of the building?
11. Outer contact of circles Construct a circle k1 (S1; 1.5 cm), k2 (S2; 2 cm), and K3 (S3; 2.5 cm) so that they are always two outer contact. Calculate the perimeter of the triangle S1S2S3.
12. Hot air balloon The center of the balloon is at an altitude of 600 m above the ground (AGL). From habitat on earth is the center of the balloon to see in elevation angle 38°20' and the balloon is seen from the perspective of angle 1°16'. Calculate the diameter of the bal
13. Alcohol How many cubic centimeters of 96% alcohol is needed to obtain 0.75 liter of 40% alcohol?
14. The pool The pool has a volume of 40 m3 and the water temperature is 20 °C. How much water at 100 °C should we pour into the pool to increase the water temperature by 5 °C?
15. Distilled water Sea water contains 5% salt. How many distilled water should be pour to 40 kg of sea water so that the salt content is 2%. How many kilograms of 2% of sea water we get?
16. Air pressure The meteorological station measured the air pressure of 1060 hPa (hectopascals). In addition to measuring instruments, there is a residential house that has a flat roof with dimensions of 10 m and 28 m. What pressure force in MN (meganewtons) force the ai
17. Gasoline How many liters of gas is in the tank if its weight 15.4kg. Specific density of gasoline is 770kg/m3.
18. Scale of map James travels one kilometer in 12 minutes. The route walked for half an hour measured on the map 5 cm. Calculate how many kilometers James walked for half an hour. Find the scale of the map.
19. Two aircraft Two planes fly to the airport. At some point, the first airplane is away from the airport 98 km and the second 138 km. The first aircraft flies at an average speed of 420 km/h, the second average speed is 360 km/h, while the tracks of both planes are perpe
20. Contract 8 employees complete the contract for 65 hours. After 17 hours, 3 employees had to leave for another job. How many more hours will the job on contract be fulfilled?

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