# Examples for 8th grade - page 86

1. Diagonals in diamons/rhombus Rhombus ABCD has side length AB = 4 cm and a length of one diagonal of 6.4 cm. Calculate the length of the other diagonal.
2. Volleyball 8 girls wants to play volleyball against boys. On the field at one time can be six players per team. How many initial teams of this girls may trainer to choose?
3. Map scale On a 1:1000 scale map is a rectangular land of 4.2 cm and 5.8 cm. What is the area of this land in square meters?
4. Content area and percents Determine what percentage is smaller cube surface, when the surface area of the wall decreases by 25%.
5. Tree trunk From the tree trunk, the diameter at the narrower end is 28 cm, a beam of square cross-section is to be made. Calculate the longest side of the largest possible square cross-section.
6. Two sisters Two sisters together have 54 CDs. 6/8 CDs has younger sister and is equal to 3/5 of CDs older sisters. How many CDs has each of the sisters?
7. Acid solution By adding 250 grams of a 96% solution of sulfuric acid to its 3% solution its initial concentration was changed to 25%. How many grams of 3% of the acid were used for dilution?
8. Boxes 200 boxes have been straightened in three rows. The first was 13 more than in the second, and in the second was one fifth more than in the third one. How many boxes are in each row?
9. Triangular prism The perpendicular triangular prism is a right triangle with a 5 cm leg. The content of the largest wall of the prism is 130 cm2 and the body height is 10 cm. Calculate the body volume.
10. Football season Dalibor and Adam together scored 97 goals in the season. Adam scored 9 goals more than Dalibor. How many goals scored each?
11. Rhombus OWES OWES is a rhombus given that OW 6cm and one diagonal measures 8cm. Find its area?
12. Water temperatures To 25 liters of water at 50 °C we add 15 liters of water at a different temperature. How many °C should the water be colder than 50 °C so that 40 liters of the water obtained has a temperature 42.5 °C?
13. Syringe and patient In 1 ampoule of 2 ml is 15 mg of Dipidol. The patient should receive 10 mg. How much ml do I draw into the syringe?
14. Washing mashine Family buy a washing machine for 350e. Cash paid 280e. What percentage of the total price must still pay the washer?
15. Tank diameter A cylindrical tank has a volume of 60 hectoliters and is 2.5 meters deep. Calculate the tank diameter.
16. Kaufland sales-off As a rule the goods to the approaching end consumption in Kaufland three days before the end of the consumption to 30% off and one day before the end of the consumption to 50% discounts. Sometimes however the seller has been mistaken and the second discoun
17. Triangle ABC Construct a triangle ABC is is given c = 60mm hc = 40 mm and b = 48 mm analysis procedure steps construction
18. Empty canister The canister is filled with oil weight 17 kg. If filled only half weight 9 kg. What weight does my empty canister have?
19. Enterprise company 30% of all employees in the enterprise are women. Men are 360 more. How many employees are in the company?
20. Hypotenuse Calculate the length of the hypotenuse of a right triangle if the length of one leg is 4 cm and its content area is 16 square centimeters.

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