# Examples for 7th grade (seventh) - page 16

1. Cubes Surfaces of cubes, one of which has an edge of 48 cm shorter than the other, differ by 36288 dm2. Determine the length of the edges of this cubes.
2. Diagonals Rhombus has two diagonals e=14 dm and f=11 dm. Calculate the side angle and height of the rhombus.
3. BMI index Calculate BMI (body mass index, an index indicating obesity, overweight, normal weight, underweight) man weighing m = 71 kg and height h = 170 cm. Index is calculated according to equation (formula): ? With BMI index is possible to compare people of diff
4. Tributaries The first tributary fill pool with water in 15 hours. The second tributary fill pool in 10 hours. For how many hours the pool is filled with both tributaries?
5. Three drivers Three driversdriving the same direction found that they have same amounth of gasoline. The first is enough to go 6 km, 4 km second and third 3km. Gasoline they divided so all three just drove to the nearest petrol station. How many km away was a petrol sta
6. Four pupils Four pupils divided \$ 1485 so that the second received 50% less than the first, the third 1/2 less than a fourth and fourth \$ 154 less than the first. How much money had each of them?
7. Rope One half of rope use Mam for packaging, half of the rest got son, half of the rest he took father and two fifths of what remained, got daughter. Remained 143 cm of rope. How long was rope at the beginning?
8. OPT What is the perimeter of a right triangle with the legs 14 cm and 21 cm long?
9. Machines In the workshop are three machines. The first is treated 250 parts for 4.7 hours, the second is treated 300 parts for 1.9 hours and the third is treated 230 parts for 4.6 hours. How long will take to make 3100 parts if worked all three machines at the.
10. The horses A couple of horses consume 88 kg of oats for 14 days. How many oats consumed 7 horses at the same consumption for 6 days?
11. Rhombus Calculate the length of the diagonal AC of the rhombus ABCD, if its perimeter is 84 dm and the other diagonal BD has length 20 dm.
12. Tank and water Cylindrical tank were poured with 3.5 liters of water. If tank base diameter is 3 dm, how height is water level in?
13. Median In the right triangle are sides a=41 dm b=42 dm. Calculate the length of the medians tc to the hypotenuse.
14. Rail turn The curve radius on the railway line is 532 m . Length of rail track on it is 818 m. How many degrees is the angle ASB, if A and B are boundary points and S is center of arc curve.
15. Series Andrew wrote this series of numbers: 1,3,7,15, .... n. Which number in the series does not belong? ?
16. Mushrooms Fresh mushrooms contain 94% water, dried 14%. How many kg of fresh mushrooms is needed to collect to get 10 kg dried?
17. Segments Which of the pairs of numbers on the number line encloses the longest segment: ?
18. Basements In the first basement is more flies than the spiders, the second vice versa. Each basement had spiders and flies together 100 feet. Determine how many could be flies and spiders in the first and second basement. PS. We only need, when you write how many.
19. Around the flowerbed Around a rectangular flowerbed with dimensions 5.25 m and 3.5 m are to be planted roses equally spaced so that the roses found in every corner of the flowerbed and consumed them as little as possible. a) At what distance are planted roses? b) How many ros
20. Elections The elections attended a total 4818 voters. First day 39 men more than women, the second day 21 women more than men. How many women attended elections?

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