# Examples for 7th grade (seventh) - page 80

1. Car crash
After a traffic accident, police measured 1.16 permille of alcohol in the driver's blood. What amount of alcohol did the driver have in the blood when about 5 kg of blood circulates in the human body?
2. Surface area 6
Find the surface area of a prism whose bases are right triangles with sides of length 3, 4, and 5 inches and a height of 8 inches. Include a sketch
3. Number with ones
The first digit of the number is 1, if we move this digit to the end we get a 3 times higher number, which is the number?
4. Dropped sheets
Three consecutive sheets dropped from the book. The sum of the numbers on the pages of the dropped sheets is 273. What number has the last page of the dropped sheets?
5. Natural gas in kWh
Gas consumption for 2017 was 11,301 kWh I paid 532 € How much 1 m3?
6. Grandfather and grandmother
The old mother is 5 years younger than the old father. Together they are 153 years old. How many years has each of them?
7. Temperature 5
Temperature outside starts at 0 Fahrenheit. Over time the temperature changes at a rate of -0.6 Fahrenheit per hour. How long will it take for the temperature to reach -4.5 Fahrenheit?
8. Two trains
There were 159 freight wagons on the railway station creating 2 trains. One had 15 more wagons than the other. How many wagons did each train have?
9. Paper box
Calculate whether 11 dm² of paper is sufficient for gluing a box without a lid with bottom dimensions of 2 dm and 15 cm and 12 cm high. Write result as: 0 = No, 1 = Yes
10. Complementary angles 2
Two complementary angles are (x+4) and (2x - 7) find the value of x
11. Water tank
What is the height of the cuboid-shaped tank with the bottom dimensions of 80 cm and 50 cm if the 480 liters of water reaches 10 cm below the top?
12. A pipe
A radius of a cylindrical pipe is 2 ft. If the pipe is 17 ft long, what is its volume?
13. Playing
How long have we trained on the pitch when we know that the warm-up took 10 minutes, we trained passes for one-third of the time and we played football half the time?
14. Iron pole
The iron pole is in the ground 2/5 of its length, partly above the ground 1/3 is yellow, and the unpainted section is 6 m long. How long is the entire column?
15. Equation 29
Solve next equation: 2 ( 2x + 3 ) = 8 ( 1 - x) -5 ( x -2 )
16. Dance group
The dance group formed groups of 4, 5, and 6 members. Always one dancer remains. How many dancers were there in the whole group?
17. Area of rectangle
How many times will increase the area of the rectangle, if we increase twice the length and at the same time we decrease the width by the half?
18. Tilapia
A fish vendor sells 5/7 kilos of tilapia for 73.50. If you will buy 2 1/7 kilos of tilapia, how much will it cost?
19. Tickets
On Monday, 33 tickets were sold. Every next day, twice as many as the previous day. How many tickets were sold on Friday and how many totally from Monday to Friday?
20. Isosceles triangle
The circumference of the isosceles triangle is 32.5 dm. Base length is 153 cm. How long is the leg of this triangle?

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