# Grade - examples - page 128

1. Owner of the company
The owner of the company with extensive administrative activity wants to sell the obsolete 3 machines at the price of CZK 1000 per 1 machine with a six-month warranty period. If the machine breaks down during this period, the owner will return the employe
2. Kangaroo
Kangaroo do 10 jumps in 1 minute and then three minutes lie , then will make 10 jumps in 1 minute and 3 minutes lie, and so on. Find the shortest time in which kangaroo do 30 jumps.
3. Dwarfs
Four dwarfs would prepare firewood for Snow White in580 minutes. After an hour and a half they recruit friends so that finished preparing the wood for 280 minutes. How many dwarfs they recruited?
4. Rectangle
Draw a rectangle with the sides a = 4 cm, b = 5 cm. Mark the center of symmetry S and all axes of symmetry. How many axes of symmetry has? Write down.
5. Parking
120 vehicles parking on the morning. Pasenger car is charged 20 CZK, 50 CZK per bus. The guard collected for parking 2640 CZK in total. How many cars and how many buses stood in the parking?
6. Unknown number
Determine the unknown number that is equal to a quarter of the fifth of number, which is by 152 more than unknown number.
7. Grass seeds
How many kg of grass seed is needed to be sowing a circular field with a diameter of 120 meters when the 1 m2 should be used 0.8 grams seeds?
8. Even / odd numbers
a / Using variable n write two consecutive odd numbers. b / the sum of three consecutive odd numbers is 333. What are this numbers?
9. Mr and Mrs
Mr. Calda and Mrs. Cald have a total of 139 years. How many years have when we know that Mr. Calda is 9 years older than Mrs. Cald
10. Billboard
Rectangular billboard is 2.5 m long with a diagonal 2.8 m long. Calculate the perimeter and the content area of the billboard.
11. Apples 2
James has 13 apples. He has 30 percent more apples than Sam. How many apples has Sam?
12. Sales stores
The first sales store passed the 1/3 and the second 2/5 of the total amount of goods.In third store passed the 2/3 rest of the goods. The remaining 40 kg of goods put into fourth store. How many kilograms of goods pass to a third store?
13. Expression 1
What is 7+8-(5×2)+5-4+(6×(5-3)+6)-(8+10)-7+6?
14. Sum or product
What is the probability that two dice fall will have the sum 7 or product 12?
15. Pears
Andrew, Lenka and Rasto have together 232 pears. Lenka has 28 more than Rasto and Rasto pears have 96 more than Andrew. Determine how much each of them has pears.
16. Class pairs
In a class of 34 students, including 14 boys and 20 girls. How many couples (heterosexual, boy-girl) we can create? By what formula?
17. Unknown number
Identify unknown number which 1/5 is 40 greater than one tenth of that number.
18. Hollow sphere
The volume of the hollow ball is 3432 cm3. What is its internal radius when the wall thickness is 3 cm?
19. Package Deal - what to choose
The parents decided to purchase a mobile phone to their son. They choose from menu: ? Which offer is best?
20. Cards
The player gets 8 cards of 32. What is the probability that it gets a) all 4 aces b) at least 1 ace

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