# Examples for 7th grade (seventh)

1. OPT
What is the perimeter of a right triangle with the legs 14 cm and 21 cm long?
2. Bottle
Bottle with wine costs 58 USD. Wine is 27 USD more expensive than the empty bottle. How much is the bottle itself?
3. Inflow - outflow
The tank will fill by inflow for 143 minutes and empties by outflow for 150 minutes. How long take to fill tank if it is also opened the inflow and outflow?
The size of two internal angles of a triangle ABC are α=6/18π and β=7/18π. Calculate the size of the third angle.
5. Square
If we increase one side of square by its one-half then square perimeter increase by 10 cm. What is the side of the square?
6. Parquet floor
Three workers laid parquet floor for 2.301 hour. The first one would do this work alone 7 hours, the second in 6 hours. For how many hours would fulfill this work the third worker, if he worked alone?
7. Simple interest
Peter put into bank 853 euros deposit. After 7 years on account overall was 984 euro. What was the interest rate if bank add simple interest?
8. Accidents
The count of accidents in 1995 caused 8780 women which is 8.4%. How many men caused the accidents?
9. Lie/do not lie
The function is given by the rule f(x) = 8x+16. Determine whether point D[-1; 8] lies on this function. Solve graphically or numerically and give reasons for the your answer.
10. 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?
11. Air
Room is 35.6 m long, 19.6 dm wide and 591 cm high. How many people can simultaneously be in this room if for hygiene reasons is calculated 5000 dm3 of air per person?
12. 7 triangle
The triangle area is 26.7 cm2. Determine the side length l if appropriate height hl = 45.3 cm.
13. Metallurgical enterprise
Metallurgical company daily produces 318 tons of cast iron. How many tons of coke it burns to melt cast iron when 10 tons of cast consumes 6 tons of coke?
14. The pot
The pot is in 1/3 filled with water. Bottom of the pot has an area of ​​329 cm2. How many centimeters rises water level in the pot after add 1.2 liters of water?
15. VAT
In the country XYZ car Daewoo Leganza costs 3748 Euros including VAT; 3335.72 Eur without VAT. a) Determine the rate of VAT. b) How much is Euro VAT paid on the purchase? c) How many % of the total price of the goods is VAT? VAT = value added tax.
16. Diplomas
Suzanne helped write out diplomas. Issuance its first took 3 minutes, each next 2.3 minutes. How much time it will take to write out n=16 diplomas (including the first), write out this pace?
17. Word problem
348 students were on holiday in Hungary. 133 bought pizza, chips 28 pupils, 25 pupils bought soda, butter 26 pupils, 15 pupils fruits, vegetables 29 students. How much pay for all the food, if every meal cost 5.3 euros?
18. Column
Perpendicular pole high 8 m tall broke and its toe fell 2.7 m from the bottom of the pole. At what height above the ground pole broke?
19. Washing machine
The price of washing machine was decreased by 21% and then by 55 € due small sales. After two price decreases cost € 343. How much was originally cost?
20. Water tank
Water tank shape cuboid has a width of 3.1 m and length twice larger. How high will reach water if water flow into 13 liters of water per second during 16 minutes?

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