Examples for 9th grade - page 9
Pizza with a diameter 41 cm have weight 531 g. What diameter will have a pizza weighing 749 g if it is make from the same cloth (same thickness....) and same decorated?
- Pyramid roof
1/3 of area of the roof shaped regular tetrahedral pyramid with base edge 10 m and height of 4 m is already covered with roofing. How many square meters still needs to be covered?
On the road sign, which informs the climb is 20%. Car goes 5 km along this road. What is the height difference that car went?
- ISO triangle
Calculate the area of an isosceles triangle KLM if the length of its sides are in the ratio k:l:m = 4:4:3 and has perimeter 128 mm.
- Cylinder - basics
Cylinder with base radius r = 37 cm and height h=74 cm. Calculate:
- Climb in percentage
The height difference between points A and B is 442 m. Calculate the percentage of route climbing if the horizontal distance places A, B is 6.8 km.
Circular cone with height h = 11 dm and base radius r = 4 dm slice plane parallel to the base. Calculate distance of the cone vertex from this plane, if solids have the same volume.
- Rotary cone
The volume of the rotation of the cone is 104 cm3 and angle between the side of the cone and base angle is 80°. Calculate lateral surface area of this cone.
- Tetrahedral pyramid
Calculate the volume and surface area of a regular tetrahedral pyramid, its height is $b cm and the length of the edges of the base is 7 cm.
At 15:20 the ship set sail at 16 km/h. At 17:50 followed by at 41 km/h sail boat. When sail boat catches up the ship? How many minutes will catch up took?
From the cottage started first group of tourists at 10:00 AM at speed 4 km/h. The second started after them 39 minutes later at speed 6 km/h. How long and how many kilometers from the cottage will catch the first group?
Cylinder shell has the same content as one of its base. Cylinder height is 25 m. What is the radius of the base of the cylinder?
- Hollow sphere
Calculate the weight of a hollow gold sphere (density 19.32 g/cm3), if the outer diameter is 18 cm and wall thickness is 4 mm.
How many m2 of copper plate should be to replace roof of the tower conical shape with diameter 13 m and the angle at the vertex of the axial section is 150°?
- Diagonals of the rhombus
Calculate height of rhombus whose diagonals are 15 cm and 5 cm.
- Triangular prism
Plane passing through the edge AB and the center of segmet CC' of regular triangular prism ABCA'B'C', has angle with base 50 degrees, |AB| = 5 cm. Calculate the volume of the prism.
- Profitable bank deposit 2012
Calculate the value of what money lose creditor with a deposit € 7700 for 4 years if the entire duration are interest 2.2% p.a. and tax on interest is 19% and annual inflation is 3.6% (Calculate what you will lose if you leave money lying idle at negative
- Gold wire
From one gram of gold was pulled wire 1.2 km length. What is it diameter if density of Au is ρ=19.5 g/cm3?
- Equilateral triangle
How long should be the minimum radius of the circular plate to be cut equilateral triangle with side 18 mm from it?
- Hexagon A
Calculate area of regular hexagon inscribed in circle with radius r=7 m.