# Examples for 7th grade (seventh) - page 26

1. Ratio three numbers Three numbers SUV are in the ratio 1:2:3. Their sum is 24. Find this numbers and write their add and sum.
2. Height UT How long is height in the equilateral triangle with a side b = 43?
3. MPG 252 miles a week fills up twice a week. Each fill is 38 gallons. What is gas mileage of the car?
4. Troops - soldiers Food stocks will last 20 soldiers of the 4-day training. How many days they could extend training if four soldiers become sick?
5. Aquarium 6 How high is the water level in the aquarium with a rectangular base 40cm and 50cm if it is filled 0,65hl of water?
6. 3-bracket 3 Two angles in a triangle are 90° and 60°. Has triangle at least two equal sides?
7. Car range Kia has an average gasoline consumption of 7.1 liters per 100 kilometers. What is the range of the car for 95 euros if fuel costs 1.6 EUR / liter, if the tank has a volume of 72 liters?
8. Coffee Coffee from the machine in the cup cost 28 cents. Coffee is 20 cents more expensive than the cup. How much is the cup?
9. Trousers Jarek bought new trousers, but the trousers were too long. Their length was in the ratio 5: 8 to Jarek height. Mother his trousers cut by 4 cm, thus the original ratio decreased by 4%. Determine Jarek's high.
10. Hall Rectangular hall will have pave by square tiles with a side length 15 cm. The hall has length 18 meters and width 3 m. How many tiles need to buy if 2 percent of the amount is disrupted during the work?
11. 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?
12. Truncated cone Calculate the volume of a truncated cone with base radiuses r1=13 cm, r2 = 10 cm and height v = 8 cm.
13. 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)?
14. Base Base of building is circle with diameter 25 m. Calculate the circumference of a circular trench witch diameter is 41 cm wider than the diameter of the base.
15. Salary Mr. Johnson's had monthly salary 955 USD since the beginning of year. From which month his salary was increased by 52 USD, when in year earned 11824 USD (enter as a number from 1 to 12)?
16. Medal Calculate the approximate weight of the gold Olympics medal, if its diameter is 8 cm and a thickness 6 mm. The density of gold find out in the tables or on the Internet.
17. Secret number Determine the secret number n, which reversed decrease by 16.4 if the number increase by 16.4.
18. Iron Iron ore contains 57% iron. How much ore is needed to produce 20 tons of iron?
19. Motion 2 At 10 o'clock started from place A car speed at 90 km/h. 20 minutes after started from the place B at speed 60 km/h another car. Distance places A and B is 120 kilometers. What time and where they meet?
20. One and a half chicken One and a half chicken bears one and a half egg in one and a half day. How many eggs can withstand from 6 chicken in 6 days?

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