# Examples for 8th grade - page 90

1. Diagonal of square
Calculate the side of a square when its diagonal is 10 cm.
2. Call of Duty
Game Call of Duty in CTF (Capture the Flag) opposes the British and the Germans, whose bases are 15 km apart. A German soldier stole the British flag and hid it with it in a secret place between the bases. If the British soldiers set out at a speed of 14.
3. Bronze medal
To produce 1 kg of bronze must be 0.95 kg copper, 0.04 kg of tin, 0.01 kg zinc. The bronze medal has a weight of 8.5 g. How much copper, tin and zinc does medal have?
4. Belgium vs Italy
Belgium played a match with Italy and Belgium win by 2 goals. The match fell a total 6 goals. Determine the number of goals scored by Belgium and by Italy.
5. Price increase 2x
If two consecutive times we increase the price of the product by 20%, how many % is higher final price than the original?
6. Potatoes bags
I have three bags with 21 kg potatoes. The first bag is 5.5 kg more than in the second bag and the third is 0.5 kg more than in the second bag. Determine how many kgs of potatoes is in each bag.
7. ATC camp
The owner of the campsite offers 79 places in 22 cabins. How many of them are triple and quadruple?
8. Three cubes
The body was created by gluing three identical cubes. Its volume is 192 cm3. What is its surface in dm2?
9. Cleaning windows
Cleaning company has to wash all the windows of the school. The first day washes one-sixth of the windows of the school, the next day three more windows than the first day and the remaining 18 windows washes on the third day. Calculate how many windows ha
10. Summerjob
Three students participated in the summerjob. Altogether they earn 1780, -. Peter got a third less than John and Paul got 100,- more than Peter. How much got every one of them?
11. Tour
35 people went on a tour and paid 8530, -. Employees pay 165, and family members 310. How many employees and how many family members went to the tour?
12. Diagonals
Given a rhombus ABCD with a diagonalsl length of 8 cm and 12 cm. Calculate the side length and content of the rhombus.
13. Collecting day
At collecting day at school pupils of three classes took total of 1063 kg of paper. Class B collected half more than A Class and class C 55 kg more than B. How many kg of paper collected each class?
14. Raw meat
In the school cafeteria for one lunch, they prepare 490 servings of 50 g of boiled meat. Meat loses 30% of its weight by cooking. How many kilograms of raw meat must the school canteen prepare for this lunch to cook?
15. Trees
Along the road were planted 250 trees of two types. Cherry for 60 CZK apiece and apple 50 CZK apiece. The entire plantation cost 12,800 CZK. How many was cherries and apples?
16. Coach
Average age of 24 players and a coach of one team is 24 years. The average age of players without a coach is 23 years. How old is the coach?
17. Two boats
The sightseeing boat sail at 25 km / h. The cruise take 6 hours. How long the another boat sails at 60 km/h?
18. UN 1
If we add to an unknown number his quarter, we get 210. Identify unknown number.
19. Conical area
A right angled triangle has sides a=12 and b=19 in right angle. The hypotenuse is c. If the triangle rotates on the c side as axis, find the volume and surface area of conical area created by this rotation.
20. Equilateral triangle ABC
In the equilateral triangle ABC, K is the center of the AB side, the L point lies on one-third of the BC side near the point C, and the point M lies in the one-third of the side of the AC side closer to the point A. Find what part of the ABC triangle conta

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