# Grade - examples - page 102

1. Pins
Sarah bought 9 pins, Eva bought 4 pins and saved 2 euros. How many pins buy Dana, when she have 3 euro?
2. Alcohol mixing
How much 55% alcohol we must pour into 1500 g 80% alcohol to form a 60% alcohol? How much 60% alcohol created?
3. Salary in enterprise
The average salary in the company is 27 000 CZK, 30% of workers have the lowest average income of 19 thousand CZK. There were an increase in the salary in this group by 2%. How much % increased the average salary across the company?
4. Rhombus and diagonals
The a rhombus area is 150 cm2 and the ratio of the diagonals is 3:4. Calculate the length of its height.
5. Master and apprentice
Master painted the roof in 3 hours and apprentice for 4 hours. How many of roof they painted in hour and how many in three quarters of an hour?
6. The rod
The rod is painted in four colors. 55% of the bar is painted in blue, green 0.2 of rod, 1/8 is brown and the remaining 45 cm of white. How long is rod?
7. Area of square
Calculate the content area of the square whose perimeter is 24 dm.
8. QuizQ2
The square of the first number is equal to three-fifths of the second number. Determine both numbers if you know that the second number is 5 times greater than the first, and neither of numbers is not equal to zero.
9. Unknown number 2
I think the number. When he reduces it four times, I'll get 11. What number am I thinking?
10. Draw a trapezoid
Draw a trapezoid if given a = 7 cm, b = 4 cm, c = 3.5 cm, diagonal AC = 5cm. Solve as a construction task.
11. The fence
I'm building a fence. Late is rounded up in semicircle. The tops of late in the field between the columns are to copy an imaginary circle. The tip of the first and last lath in the field is a circle whose radius is unknown. The length of the circle chord i
12. Chord 3
What is the radius of the circle where the chord is 2/3 of the radius from the center and has a length of 10 cm?
13. Compound interest
Compound interest: Clara deposited CZK 100,000 in the bank with an annual interest rate of 1.5%. Both money and interest remain deposited in the bank. How many CZK will be in the bank after 3 years?
14. Divide money 2
Ben and Dan had the same amount of money at the start. When Ben gave 300 to Dan, the ratio of Ben 's money to Dan's money became 2:3. How much money did each have at first?
15. Fan
The fan has a speed of 210 RPM. Calculate for time of one fan period.
16. Kitchen
Kitchen roller has a diameter 70 mm and width of 359 mm. How many square millimeters roll on one turn?
17. Park
In the park is marked diamond shaped line connecting locations A, D, S, C, B, A. Calculate its length if |AB| = 108 m, |AC| = 172.8 m.
18. Class
The class has 18 students. Everyone knows inline skating or skateboarding. Inline skating can ride 11 students on a skateboard 10. How many ride on inline skates and on skateboard?
19. Bookshelve
Bookshelve with an original price of € 200 twice become cheaper. After the second discounted by 15% the price was € 149.60. Determine how much % become cheaper for the first time.
20. Juice box
In the box is 0.3 liters of juice. How many liters of juice contains 3 these boxes?

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