# Examples for 7th grade (seventh) - page 52

1. Painter How many euros we will pay for repainting the room shaped cuboid with a length of 4.5 meters, width of 2.5 meters and a height of 3 meters, if for 1 m2 with paint we pay € 1.5?
2. The tram The tram is moving with acceleration a = 0.3m/s2. How long it will pass the first meter of track? How long does it take 10 meters. What is its speed at the end of the 10 meters track?
3. Divisibility Write all the integers x divisible by seven and eight at the same time for which the following applies: 100
4. Athlete How long length run athlete when the track is circular shape of radius 120 meters and an athlete runs five times in the circuit?
5. Pulley On wheels with a diameter of 40 cm is fixed rope with the load. Calculate how far is load lifted when the wheel turns 7 times?
6. Octagonal mat Octagonal mat formed from a square plate with a side of 40 cm so that every corner cut the isosceles triangle with leg 3.6 cm. What is the content area of one mat?
7. Three digits number 2 Find the number of all three-digit positive integers that can be put together from digits 1,2,3,4 and which are subject to the same time has the following conditions: on one positions is one of the numbers 1,3,4, on the place of hundreds 4 or 2.
8. Concrete pipe How much will cost cover a 6 m long concrete pipe with an outer radius 1.5 m and inner radius 0.8 meters if 1 m2 paint costs 24 €.
9. One-third A one-third of unknown number is equal to five times as great as the difference of the same unknown number and number 28. Determine the unknown number.
10. Internal angles One internal angle of the triangle JAR is 25 degrees. The difference is the size of the two other is 15°. Identify the size of these angles.
11. Two rulers We have two rulers. Scale interval on first rulers are a spaced 1 cm and on second spaced 15 mm. Rulers are attached to each other so that they match initial divider commas. What next dividers commas coincide? Find at least three cases.
12. Store Peter paid in store 3 euros more than half the amount that was on arrival to the store. When he leave shop he left 10 euros. How many euros he had upon arrival to the store?
13. Alarm clock The old watchmaker has a unique digital alarm in its collection that rings whenever the sum of digits of the alarm is equal to 21. Find out when the alarm clock will ring. What is their number? List all options . ..
14. Bridge piers One quarter of the bridge pier is sunk into the ground. Two thirds are in the water. Protruding above the water is 1.20 m long. Determine the height of bridge piers.
15. Chicks How many chicks were hatched from 4500 eggs, when an average of 100 eggs hatched 87 chicks?
16. Ratios Divide: a) 250 CZK in the ratio 2:3 b) 1000 CZK in the ratio 4:7:9
17. Bicycle wheel Bicycle wheel diameter is 62 cm. How many times turns the bicycle on the road 1 km long?
18. Divisibility by 12 Replace the letters A and B by digits so that the resulting number x is divisible by twelve /find all options/. x = 2A3B How many are the overall solutions?
19. Trees 3/5 trees are apples, cherries are 1/3. 5 trees are pear. How many is the total number of trees?
20. Ornamental shrubs Children committed to plant 240 ornamental shrubs. Their commitment however exceeded by 48 shrubs. Write ratio of actually planted shrubs and commitment by lowest possible integers a/b.

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