# Examples for 7th grade (seventh)

1. Distance of numbers
Which number has the same distance from the numbers -5.65 and 7.25 on the numerical axis?
2. Bronze medal
To produce 1 kg of bronze must be 0.95 kg copper, 0.04 kg of tin, 0.01 kg zinc. The bronze medal has a weight of 8.5 g. How much copper, tin and zinc does medal have?
3. Earth and Sun
Earth is 150 million km away from the Sun, 300,000 km of sunlight travels in 1 second. How long will the light come from the Sun to the Earth?
4. School 6
Jirka lives 600m from the school, Honzík 1200m. How many kilometers a week does Honzik go over Jirka on his way to school and back? How many times more Honzík will go than Jirka?
5. Steps
Walkway from the house to the school is 180 m long. How many more steps Michael makes than his father on the way to school, if the length of Michael's step is 60 cm and the length of his father's step is 90 cm.
6. Railway wagon
The railway wagon holds 75 m3 load. Wagon can carry a maximum weight of 30 tonnes. What is the maximum density that may have material with which we could fill this whole wagon? b) what amount of peat (density 350 kg/m3) can carry 15 wagons?
7. Syringe and patient
In 1 ampoule of 2 ml is 15 mg of Dipidol. The patient should receive 10 mg. How much ml do I draw into the syringe?
8. Have solution
The sum of four consecutive even numbers is 96. Determine these numbers.
9. Rectangle
Find the dimensions of the rectangle, whose perimeter is 108 cm and the length is 25% larger than the width.
10. Real estate
Residential house has three entrances numbered by odd numbers arithmetic progression. The sum of the two numbers on the corner entrances is 50. Calculate the highest of this three numbers.
11. Diagonals
Draw a square ABCD whose diagonals have a length of 6 cm
12. Cubes
Carol with cut bar 12 cm x 12 cm x 135 cm to the cubes. Find the sum of all the surfaces of the resulting cubes.
13. Gasoline
How many liters of gas is in the tank if its weight 15.4kg. Specific density of gasoline is 770kg/m3.
14. Pizza 4
Marcus ate half pizza on monday night. He than ate one third of the remaining pizza on Tuesday. Which of the following expressions show how much pizza marcus ate in total?
15. Rhombus
If we increase the rhombus side by 2.4 cm; its perimeter is 20 cm. How long was the side of the rhombus?
16. Square
Calculate the perimeter and the area of square with a diagonal length 30 cm.
17. Perimeter to area
Calculate the area of a circle with the perimeter 15 meters.