# Grade - examples - page 97

1. Strange x For what x is true ??
2. Isosceles triangle Calculate area and perimeter of an isosceles triangle ABC with base AB if a = 6 cm, c = 7 cm.
3. 3 days Worker checked 2,950 products in 3 days. Second day checked 25% more than the first day. The third day 15% more products than the second day. How many products he checked in each day.
4. Waiting room In the waiting room are people and flies. Together they have 15 heads and 50 legs (fly has 6 legs). How many people and flies are in the waiting room?
5. Price reduction Price of camera is 654 USD on sale its price reduced to 411 USD. Calculate the percentage reduction in the price of the camera.
6. Volume of three cuboids Calculate the total volume of all cuboids for which the the size of the edges are in a ratio of 1:2:3, and one of the edges has a size 6 cm.
7. Candelas We burned two unequally thick and long candles. Longer burnt for three and a half hours and shorter for five hours. After two hours of burning it was identical. How many times was longer candle longer then shorter?
8. Body diagonal Cuboid with base 7cm x 3,9cm and body diagonal 9cm long. Find the height of the cuboid and the length of the diagonal of the base, It is given a quadratic function y = -4x2+5x+c with unknown coefficient c. Determine the smallest integer c for which the graph of f intersects the x-axis at two different points.
10. Speedometer The speedometer of a car reads 66 km/h. It's accurate to within 4.1% What is the maximum possible error?
11. Playing Cards Kara has 2 times more cards than Dana, Dana has 4× less than Mary. Together they have 728 cards. How many cards has each of them?
12. Book John read the book so that it read 30 pages per day. Maxim read 34 pages a day and read it two days earlier than John. How many pages has the book?
13. Rhombus PQRS is a rhombus. Given that PQ=3 cm & height of rhombus is given 2 cm. Calculate its area.
14. Dusan a) Dusan break two same window, which has triangular shape with a length of 0.8 m and corresponding height 9.5 dm. Find how many dm2 of glass he needs to buy for glazing of these windows. b) Since the money to fix Dusan has not, must go to the paint job
15. Reservoir 6 m long reservoir has a diameter of 2.2 m. What is its surface area in square meters?
16. Children Less than 20 children is played various games on the yard. They can create a pairs, triso and quartets. How many children were in the yard when Annie came to them?
17. 5 pumps Five pump to pump 3 hours 1600 hl of water. How long pumped same amount of water 4 pumps?
18. Dog Dog is tied to a chain, which is mounted in a corner of the yard. Yard has the shape of a square with a side length of 20 meters. The same long is also dogchain. Are there places in the yard where dog can't reach?
19. Letters The school children have written 20 letters afternoon and then threw 20 letters and then the teacher counted the children and the children were 22 so they went to throw for 2 sheets. How many letters sent together?
20. Average speed What is the average speed you have to move the way around the world in 80 days? (Path along the equator, round to km/h).

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.