# Examples for 8th grade - page 66

- Railway wagon

The railway wagon holds 75 m^{3}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? - Chord distance

The circle k (S, 6 cm), calculate the chord distance from the center circle S when the length of the chord is t = 10 cm. - Double percent

What is 30% of 80% of 3200? - Rain

How many mm of water rained the roof space 75 m^{2}if the empty barrel with a radius of 8 dm and height 1.2 m filled to 75% its capacity? :-) - Inscribed circle

XYZ is right triangle with right angle at the vertex X that has inscribed circle with a radius 5 cm. Determine area of the triangle XYZ if XZ = 14 cm. - Typing course

Before taking a typing course, Terrence could type 39 words per minute. By the end of the course, he was able to type 68 words per minute. Find the percent increase. - Trapezoid v3

The isosceles trapezoid has the angle at a firsst base 40 degrees less than the angle at second base. How large angles has this trapezoid ? - Sweets

3 chocolate and 7 cakes cost 85, - CZK. 2 chocolates and 6 cakes cost 86, - CZK. How much is 5 chocolates and 9 cakes? I wonder how to get the result, but only by logic without the use of a system of equations - Diamond

Calculate the length of the two diagonals of the diamond if: a = 13 cm v = 12 cm - Parcel

parcel has a rectangular shape of a trapezoid with bases 12 m and 10 m and a height 8 m. On parcel was built object with a footprint an isosceles triangle shape with side 4 m and height three-quarters of a meter. What is the area of unbuild parcel? - Cube

Calculate the surface of the cube ABCDA'B'C'D' if the area of rectangle ACC'A' = 344 mm^{2.} - Saving

The boy has saved 50 coins € 5 and € 2. He saved € 190. How many were € 5 and how many € 2? - Sides od triangle

Sides of the triangle ABC has length 4 cm, 5 cm and 7 cm. Construct triangle A'B'C' that are similar to triangle ABC which has a circumference of 12 cm. - Tiles

How many tiles of 20 cm and 30 cm can build a square if we have a maximum 100 tiles? - Cenda and Pepa

Cenda and Pepa went to the event. Cenda started alone. Canda started after him for 20 minutes. How long took Cenda to catch him? Cenda traveling at 15 km/h, and Pepa traveling at 25 km/h. - Scale of the map

Determine the scale of the map if the actual distance between A and B is 720 km and distance on the map is 20 cm. - Aquarium volume

The aquarium has a cuboid shape and dimensions a = 0.3 m, b = 0.85 m, c =? , V = ?. What volume has a body, if after dipping into the aquarium water level rises by 28 mm? - The farmer field

The field has paralleogram shape with dimensions side a = 80 m and height 296 m. Two and two sides is at angle 80°. Calculate acreage of field in hectares. - Coins

In ticket maschine were together one hundred coins. They were only 20 and 50 cent coins. The sum total was 29 euros and 60 cents. How many were in ticket maschine coins and which type? - Car and cyclist

Cyclist started from town at speed 18 km/h. After 1 hour 30 min started the car from town and caught up with the cyclist in 50 minutes. How fast was a car?

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