Grade - examples - page 80

1. Pencils
Emil has 23 pencils in a pencil case, 18 of which were broken. Emily 9 trims, 2 breaks, 4 trims and goes to school. When he return from school, he has broken 5 pencils. How many pencils have trimed at school?
2. Cube corners
From cube of edge 14 cm cut off all vertices so that each cutting plane intersects the edges 1 cm from the nearest vertice. How many edges will have this body?
3. Motor oil
30 liters of oil cost 28.80 Euros. How much cost a liter?
4. Right angled triangle 2
LMN is a right angled triangle with vertices at L(1,3), M(3,5) and N(6,n). Given angle LMN is 90° find n
5. Buses
Buses Ikarus and Karosa simultaneously started at 8:00 from the final station. Ikarus is returned to the station after 30 minutes. Karosa after 45 minutes. At what time both buses again returned to the station?
6. Sails
We known heights 220, 165 and 132 of sail. It has triangular shape. What is the surface of the sail?
7. Container with water
The weight of a container with water is 2.48 kg. If the cast 75% water, the container with water has a weight of 0.98 kg. Determine the weight of the empty container. How much water was originally in the container?
8. Numbers
Find number on thenumber line that has same distance from this numbers:
9. Triangle ABC
Triangle ABC has side lengths m-1, m-2, m-3. What has to be m to be triangle a) rectangular b) acute-angled?
10. Chess
How many different ways can initiate a game of chess (first pass)?
11. The city 2
Today lives 167000 citizens in city. How many citizens can we expect in 11 years if their annual increase is 1%?
12. Bathroom
How many CZK we pay for lining the perimeter walls of the bathroom with rectangular shape with dimensions 3.5 m and 4 m, high 1.5 m if 1 square m tile cost 300 CZK?
13. Pool 3
How long will fill pool cuboid shape (8m 6m 1.5m) when flows 15 liters/s?
14. College
At the college are at 57 rooms 194 students. Some rooms are triple and some quad. How many triple and quadruple rooms there is, if it is all fully occupied?
15. Rings groups
27 pupils attend some group; dance group attends 14 pupils, 21 pupils sporty group and dramatic group 16 pupils. Dance and sporting attend 9 pupils, dance and drama 6 pupil, sporty and dramatic 11 pupils. How many pupils attend all three groups?
16. Plums
In the bag was to total 136 plums. Igor took 3 plums and Mary took 4/7 from the rest. How many plums remained in the bag?
17. A three-digit numbers
Determine the total number of positive three-digit numbers that contain a digit 6.
18. Divisibility 2
How many divisors has integer number 13?
19. Water reservoir
The water reservoir is filled through one inlet 4 hours later than both together, then another inlet 9 hours later than both together. For how long is filled by each separately?
20. Colors
Willie got birthday 6 colour pens in different colors. How many ways he can give them side by side in pencil?

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