# Grade - examples - page 101

1. Speedometer
The speedometer of a car reads 66 km/h. It's accurate to within 4.1% What is the maximum possible error?
2. Isosceles triangle
Calculate area and perimeter of an isosceles triangle ABC with base AB if a = 6 cm, c = 7 cm.
3. 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.
4. 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?
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.
6. 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?
7. 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?
8. 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?
9. 5 pumps
Five pump to pump 3 hours 1600 hl of water. How long pumped same amount of water 4 pumps?
10. Rhombus
PQRS is a rhombus. Given that PQ=3 cm & height of rhombus is given 2 cm. Calculate its area.
11. Reservoir
6 m long reservoir has a diameter of 2.2 m. What is its surface area in square meters?
12. 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
13. Alcohol 2
Two types of alcohol one 63% and second 75% give 20 liters of 69% alcohol. How many liters of each type are in the mixture?
14. 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).
15. Mr. Vojta
Mr. Vojta put in the bank 35000 Kč.After a year bank him credited with interest rate of 2% of the deposit amount. How then will Mr. Vojta in the bank?
16. 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,
17. 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?
18. The port
Four ships Berthed in the port. Together sail from a port. The first ship will return to port every two weeks, second ship after 4 weeks, third after 8 weeks and fourth ship after 12 weeks. After how many weeks all the boats gather at the port?
19. Triangle IRT
In isosceles right triangle ABC with right angle at vertex C is coordinates: A (-1, 2); C (-5, -2) Calculate the length of segment AB.
20. Cone
Into rotating cone with dimensions r = 8 cm and h = 8 cm incribe cylinder with maximum volume so that the cylinder axis is perpendicular to the axis of the cone. Determine the dimensions of the cylinder.

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