Examples for 7th grade (seventh) - page 52

1. 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 €.
2. 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.
3. 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.
4. 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?
5. 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.
6. Alarm clock The old watchmaker has a special 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 ...
7. 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.
8. Chicks How many chicks were hatched from 4500 eggs, when an average of 100 eggs hatched 87 chicks?
9. Ratios Divide: a) 250 CZK in the ratio 2:3 b) 1000 CZK in the ratio 4:7:9
10. Bicycle wheel Bicycle wheel diameter is 62 cm. How many times turns the bicycle on the road 1 km long?
11. 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?
12. Trees 3/5 trees are apples, cherries are 1/3. 5 trees are pear. How many is the total number of trees?
13. 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.
14. Pumps A and B Pump A fill the tank for 12 minutes, pump B for 24 minutes. How long will take to fill the tank if he is only three minutes works A and then both pumps A and B?
15. Prism - eq triangle Calculate the volume and surface of the prism with the base of an equilateral triangle with side a = 4cm and the body height is 6cm.
16. Sidewalk The city park is a circular bed of flowers with a diameter of 8 meters, around it the whole length is 1 meter wide sidewalk . What is the sidewalk area?
17. Conference 148 is the total number of employees. The conference was attended by 22 employees. How much is it in percent?
18. Expressions Expression (3a-7).(3a+7) is identical with: ?
19. Circumscribed circle to square Find the length of a circle circumscribing a square of side 10 cm. Compare it to the perimeter of this square.
20. Cylinder twice If the radius of the cylinder increases twice, and the height is reduced twice, then the volume of the cylinder increases (how many times?):

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