# Units - examples - page 57

1. Tank 9
The tank with volume V is filled with one pump for three hours and by second pump for 5 hours. When both pumps will run simultaneously calculate: a) how much of the total volume of the tank is filled in one hour b) for how long is the tank full
2. Colour - billboard
Shelftalker has the shape of a parallelogram. Its length is 4.9 m and the corresponding height is 3.5 meters. Calculate how much (kg) paint must purchase to redecoration if 1 kg cover 4 m2 of shelftalker surface.
3. Pump
From the pump in the yard dripping water. Every drop is 1 ml. How many drops will be necessary before filling a bucket with a volume of 10 l? Calculate how long it will fulfill the bucket when drops fall each second.
4. Turtles Žofka and Julka
Gray wolf kept in his tent turtles Žofka and Julka, which together have 200 years. After 50 years will Julka 2 times older than Žofka. How old are the turtles?
5. Television
When we add to the difference between the numbers 1704 and 654 the difference numbers 14920 and 14042, we get a year in which television was invented. How many years people known the TV?
6. Cube 9
What was the original edge length of the cube if after cutting 39 small cubes with an edge length 2 dm left 200 dm3?
7. Draw it!
Draw two lines c, d that c || d. On line c mark the points A, B. By point A lead perpendicular line to c. By point B lead perpendicular line to c.
8. Money borrow
Ms. Kate wants to borrow € 2,000. The company A will borrow ten installments of 240 euros and the first two months does not pay anything. Company B it their position in 12 installments of € 210. Which company has the more favorable interest rate for Ms. K
9. Painting school
Redecoration school had scheduled for four crew to 10 days. After two days a single worker ill. For how many days the school was painted when remain workers working with the same tempo?
10. Cuboid - volume, diagonals
The length of the one base edge of cuboid a is 3 cm. Body diagonal is ut=13 cm and diagonal of cuboid's baseis u1=5 cm. What is the volume of the cuboid?
11. Holiday SMS
Kucera and Malek start from the holiday together. They agreed that if they be 100 km apart, will send a SMS. Kucera traveling at 60 km/h., Malek 90 km/h. They started at 14 hours PM. At what time they send a message?
12. Support colum
Calculate the volume and surface of the support column that is shaped as perpendicular quadrangular prism whose base is a rhombus with a diagonals u1 = 102 cm u2 = 64 cm. Column height is 1. 5m.
13. Washing machine
The price of washing machine was decreased by 21% and then by 55 € due small sales. After two price decreases cost € 343. How much was originally cost?
14. Three friends
Peter is eight times older than Rado, Rado is 3 times younger than Joseph. Together they have 120 years. Determine how many are each of them.
15. Water flow
How much water flow in pipe with a diameter of 16 cm in 1 hour if the water velocity is 2.5 m/s?
16. Pins
Sarah bought 9 pins, Eva bought 4 pins and saved 2 euros. How many pins buy Dana, when she have 3 euro?
17. Internal angles IST
Determine internal angles of isosceles trapezium ABCD /a, c are the bases/ and if: alpha:gamma = 1:3
18. Alcohol mixing
How much 55% alcohol we must pour into 1500 g 80% alcohol to form a 60% alcohol? How much 60% alcohol created?
19. Master and apprentice
Master painted the roof in 3 hours and apprentice for 4 hours. How many of roof they painted in hour and how many in three quarters of an hour?
20. Cube volume
The cube has a surface of 384 cm2. Calculate its volume.

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