# Examples for 7th grade (seventh) - page 27

1. Homework
In the crate are 18 plums, 27 apricot and 36 nuts. How many pieces of fruit left in the crate when Peter took 8 ninth: 1. nuts 2. apricots 3. fruit 4. drupe
2. Mr Novak
Mr Novak earns an average 1249 euros. When increasing the salary they gave him a choice: ? What is better choice for Mr Novak?
3. Trunk
Calculate length of the biggest fishing rod can be inserted into the trunk of a car with dimensions 165 x 99 × 85 cm?
4. Square
Rectangular square has side lengths 183 and 244 meters. How many meters will measure the path that leads straight diagonally from one corner to the other?
5. Ski lessons
On the ski course leaves 80 pupils. They live in triple and quadruple rooms. Count if rooms is the 23. How many are triple and quadruple rooms?
6. Barrel with liquid
Barrel with grain weight 297 kg. When it shed 48% of grain, ha weight 174 kg. What is the weight of empty barrel?
7. Cups
We have three cups. In the cups we had fluid and boredom we started to shed. 1 We shed one-third of the fluid from the second glass into the first and third. 2 Then we shed one quarter cup of liquid from the first to the second and to the third. 3 Then
8. Product
The sum and the product of three integers is 6. Write largest of them.
9. Floating floor
In the new building is considered a floating floor worker in each room. 30 minutes lay 9 m2 of the floor. How long 3 workers laid the floor in 4 rooms with a total area of 90 m2?
10. Tetrahedral prism
The height of a regular tetrahedral prism is three times greater than the length of the base edge. Calculate the length of the base edge, if you know that the prism volume is 2187 cm3.
11. Annulus
The radius of the larger circle is 8cm, the radius of smaller is 5cm. Calculate the contents of the annulus.
12. Inflow - outflow
The tank will fill by inflow for 143 minutes and empties by outflow for 150 minutes. How long take to fill tank if it is also opened the inflow and outflow?
13. Percentage of waste
In a square plate with side 75 cm we cut 4 same circles. Calculate the percentage of waste.
14. News
From 28 students buy magazine 10 The economist students, 10 Pravda students and 18 students don't buy any of these magazines. How many students buy both magazines?
15. Stairs
Between adjacent levels are 15 stairs. If step will be 1.2 cm lower there would be 16 stairs. What is the stair height?
16. 6 regular polygon
It is given 6 side regular polygon whose side is 5 cm. Calculate its content area. Compare how many more cm2 (square centimeters) has a circle in which is inscribed the 6-gon.
17. Cars motion
From point A car start at the speed of 90 km/h. Against it departs from the point B at the same time another car at 60 km/h. For how long and where they met if the distance between A and B is 180 km?
18. Nine balls
Imagine that you have exactly the same appearance nine balls of which one has a greater mass than the other. You have isosceles weights. Post a procedure as you would using a weights to discover heavier balls. How many measurements at least you have to do?
19. Water level
The glass container has a cuboid shape with dimensions of the bottom 24 cm and 12 cm. The height of water is 26 cm. Calculate the volume of the body, which are sunk into the water if the water level rise by 3 cm.
20. Slope
Calculate the slope of a line that intersects points (-84,41) and (-76,-32).

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