# Examples for 7th grade (seventh) - page 53

1. Ornamental shrubs Children committed to plant 240 ornamental shrubs. Their commitment however exceeded by 48 shrubs. Write ratio of actually planted shrubs and commitment by lowest possible integers a/b.
2. Pumps A and B Pump A fill the tank for 12 minutes, pump B for 24 minutes. How long will take to fill the tank if he is only three minutes works A and then both pumps A and B?
3. Prism - eq triangle Calculate the volume and surface of the prism with the base of an equilateral triangle with side a = 4cm and the body height is 6cm.
4. Conference 148 is the total number of employees. The conference was attended by 22 employees. How much is it in percent?
5. Sidewalk The city park is a circular bed of flowers with a diameter of 8 meters, around it the whole length is 1 meter wide sidewalk . What is the sidewalk area?
6. Expressions Expression (3a-7).(3a+7) is identical with: ?
7. Circumscribed circle to square Find the length of a circle circumscribing a square of side 10 cm. Compare it to the perimeter of this square.
8. Cylinder twice If the radius of the cylinder increases twice, and the height is reduced twice, then the volume of the cylinder increases (how many times?):
9. MO 2016 Numerical axis Cat's school use a special numerical axis. The distance between the numbers 1 and 2 is 1 cm, the distance between the numbers 2 and 3 is 3 cm, between the numbers 3 and 4 is 5 cm and so on, the distance between the next pair of natural numbers is always in
10. Jam Jar with jam weighs 800 grams. Jam weighs three times as much as the empty glass. What is the weight of jam that is in the glass?
11. The percentages in practice If every tenth apple on the tree is rotten it can be expressed by percentages: 10% of the apples on the tree is rotten. Tell percent using the following information: a. in June rained 6 days b, increase worker pay 500 euros to 50 euros c, grabbed 21 fro
12. Unknown number 7 16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number.
13. Timeage Seven times of my age is 8 less than the largest two-digit number. How old I am?
14. Sales of products For 80 pieces of two quality products a total sales is 175 Eur. If the first quality product was sold for n EUR per piece (n natural number) and the second quality product after 2 EUR per piece. How many pieces of the first quality were sold?
15. Bus lines Buses connections are started from bus stop on its regular circuit as follows: No. 27 bus every 27 minutes and No.18 every half hour. What time started this two bus lines run if the bus stop met at 10:15 am.?
16. Performance Same number of tickets sold for 15 CZK, 20 CZK, 30 CZK and 40 CZK a total of CZK 13,230 on theatre performance. How many tickets were sold for this performance?
17. Mr. Happy Mr. Happy planted 36.6 meters square gardens grass; It's a third of the garden more than half of the garden. What is square area of this garden?
18. Field on plan Plan has a scale of 1: 2500.Determine dimensions in centimeters which will have on plan field with a length of 310 meters and a width of 182.5 meters.
19. Type of triangle How do I find the triangle type if the angle ratio is 2:3:7 ?
20. Rhombus EFGH Construct the rhombus EFGH where e = 6.7cm, height to side h: vh = 5cm

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