# Latest problems - page 21

1. Soup from canteen For how many people is 90 liters of soup enough if we assume 3/8 liter of soup per person in the canteen?
2. On line On line p: x = 4 + t, y = 3 + 2t, t is R, find point C, which has the same distance from points A [1,2] and B [-1,0].
3. Center of line segment Calculate the distance of the point X [1,3] from the center of the line segment x = 2-6t, y = 1-4t ; t is .
4. Left handed It is known that 25% of the population is left-handed. What is the probability that there is a maximum of three left-handers at a seminar where there are 30 participants?
5. Inlet and outlet The pool has a capacity of 50 hl. The inlet pipe flows in 1 minute 1.25 hl, and the waste pipe outlet is draining the full pool in 50 minutes. How long will take the empty the full pool when both the inlet and outlet are opened at the same time?
6. Cris had Cris had 15000 . He spent 1/3 of his money on a table and the remaining on 5 similar chairs that cost the same. How much did one chair cost?
7. Two ships The distance from A to B is 300km. At 7 am started from A to B a ferry with speed higher by 20 km/h than a ship that leaves at 8 o'clock from B to A. Both met at 10h 24min. Determine how far they will meet from A and when they reach the destination.
8. Grandma Grandma bought two 10 pack of eggs. She used 8 eggs on the cake, 2 times less on the omelette and 4 more eggs for breakfast. How many eggs did it stand for?
9. The sales The sales tax rate is 4.447​% for the city and 4​% for the state. Find the total amount paid for 2 boxes of chocolates at ​\$17.96 each.
10. Coordinates of vector Determine the coordinate of a vector u=CD if C(19;-7) and D(-16;-5)
11. 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?
12. Soldier An experienced soldier digs a good trench in 30 hours. Two soldiers dug the same trench each 40 hours. How many hours will the ditch dig all three together?
13. Component fail There is a 90 percent chance that a particular type of component will perform adequately under high temperature conditions. If the device involved has four such components, determine the probability that the device is inoperable because exactly one of the.
14. The third The one-third rod is blue, one-half of the rod is red, the rest of the rod is white and measures 8 cm. How long is the whole rod?
15. Construct Construct a triangle ABC inscribed circle has a radius r = 2 cm, the angle alpha = 50 degrees = 8 cm. Make a sketch, analysis, construction and description.
16. MO C–I–1 2018 An unknown number is divisible by just four numbers from the set {6, 15, 20, 21, 70}. Determine which ones.
17. Cylindrical tank 2 If a cylindrical tank with volume is used 12320cm raised to the power of 3 and base 28cm is used to store water. How many liters of water can it hold?
18. MO Z8-I-1 2018 Fero and David meet daily in the elevator. One morning they found that if they multiply their current age, they get 238. If they did the same after four years, this product would be 378. Determine the sum of the current ages of Fero and David.
19. Prime number Jan wrote any number from 1 to 20. What is the probability that he wrote the prime number?
20. Powers 3 2 to the power of n divided by 4 to the power of -3 equal 4. What is the vaule of n?

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