# Grade - examples - page 127

1. One green In the container are 45 white and 15 balls. We randomly select 5 balls. What is the probability that it will be a maximum one green?
2. Consecutive numbers Sum of ten consecutive numbers is 105. Determine these numbers (write first and last).
3. 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
4. Unknown number 7 16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number.
5. Students In the front row sitting three students and in every other row 11 students more than the previous row. Determine how many students are in the room when the room is 9 lines, and determine how many students are in the seventh row.
6. Timeage Seven times of my age is 8 less than the largest two-digit number. How old I am?
7. 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?
8. 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.?
9. 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? Add marks (+, -, *, /, brackets) to fullfill equations 1 3 6 5 = 10 This is for the 4th grade of the primary school - with no negative numbers yet
11. Insert into GP Between numbers 5 and 640 insert as many numbers to form geometric progression so sum of the numbers you entered will be 630. How many numbers you must insert?
12. Asymptote What is the vertical asymptote of ?
13. 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.
14. Type of triangle How do I find the triangle type if the angle ratio is 2:3:7 ?
15. Rhombus EFGH Construct the rhombus EFGH where e = 6.7cm, height to side h: vh = 5cm
16. Triangle angles In a triangle ABC the interior angle at the vertex C is twice as the internal angle at the point A. Outer angle at the point B measured 117 degrees. How big is the outer angle at the vertex A?
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. Ski tow The ski club has 168 pupils and used lift with 60 seats, while students always follow the same sequence in filling seats. How many times while riding a ski lift skier sitting in the same seat as the first run?
19. Brick Brick weight before drying is 5.3 kg. After drying, the bricks is 1 kg lighter and after firing is 0.7 kg lighter than after drying. What is the weight of the brick after drying and firing?
20. Pipe cross section The pipe has an outside diameter 1100 mm and the pipe wall is 100 mm thick. Calculate the cross section of this pipe.

Do you have an interesting mathematical example that you can't solve it? Enter it, and we can try to solve it.

To this e-mail address, we will reply solution; solved examples are also published here. Please enter e-mail correctly and check whether you don't have a full mailbox.