# Examples for 7th grade (seventh)

1. Cone and the ratio
Rotational cone has a height 23 cm and the ratio of the base surface to lateral surface is 7: 9. Calculate a surface of the base and the lateral surface.
2. Wheel
How many times turns the wheel of a passenger car in one second if car run at speed 100 km/h. Wheel diameter is d = 62 cm.
3. Hiker
Hiker went half of trip the first day, the third of trip the second day and remaines 15 km. How long trip he planned?
4. Decomposition
Make decomposition using prime numbers of number 155. Result write as prime factors (all, even multiple)
5. Garden
Father dig up the garden in 9 hours. Son in 13 hours. How many hours take dig up the garden together?
6. Rounding
The following numbers round to the thousandth:
7. Christmas
Exactly after 114 hours we sit down to Christmas Eve table. What day and what time it was when Dad said this sentence. The Christmas Eve table they sit down exactly on the 18-o'clock (6 PM).
8. Cars
Cars started at 7:00 AM. From point A car run at 40 km per hour, from B car run 70 km per hour. Between A and B is 250 km long road. When and where will meet (measured from point A)?
9. Soup
47% of pupils at the school to eat in the canteen, 1/47 of students who eat in the canteen eat lunch soup. a) What percentage of pupils who eat in the canteen and eat soup for lunch? b) What percentage of all pupils of school eat lunch soup?
10. Sales off
Calculate what was the original price of the good, if the price after discount 25% and the subsequent rise of 20% is 400 USD.
11. Playing Cards
Kara has 2 times more cards than Dana, Dana has 4× less than Mary. Together they have 728 cards. How many cards has each of them?
12. Pigs
Pigs are feed by beet.Beet feed containing 12% dry solids, which is 0.72% of digestible crude protein. How much beet must beconsumed in one month (30 days), if the weight of digestible crude protein contained in a daily dose of beet was 0.912 kg?
13. Rectangle - sides 3
If in the rectangle ABCD we enlarge the side a by 5 cm and decrease the side b by 2 cm, the rectangle area will be reduced by 5 cm². When we decrease the length of the side a by 4 cm and and at the same time we increase the length of side b by 3 cm we inc
14. Ladder
8.3 meters long ladder is leaning against the wall of the well, and its lower end is 1.2 meters from this wall. How high from the bottom of a well is the top edge of the ladder?
15. Bouquet
Gardener tying bouquet of flowers for 8 and none was left. Then he found that he could tying bouquet of 6 flowers and also none was left. How many have gardener flowers (minimum and maximum) if they had between 50 and 100 flowers?
16. Segments
Line segments 62 cm and 2.2 dm long we divide into equal parts which lengths in centimeters is expressed integer. How many ways can we divide?
17. Percentage reduction
Reducing the unknown number by 19% get number 700.7 Determine unknown number.
18. Roots
Calculate the square root of these numbers:
19. Dog II
Journey from a rangers' home to the town is 6 km. Mr. ranger started from his home and went 3 km per hour. His women came from the town and also went 3 km per hour. With ranger started dog and runs in 12 km in 1 hour. The dog went to ranger's women then
20. Liters in cylinder
Determine the height at which level 24 liters of water in a cylindrical container having a bottom diameter 36 cm.

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