Examples for 8th grade - page 17
Within a regular pentagon ABCDE point P is such that the triangle is equilateral ABP. How big is the angle BCP? Make a sketch.
Between the two ports on the river is going steamship. The journey there and back takes 14:49. Downstream steamship traveling at 21 km/h, upstream 9 km/h. What is the distance between the ports?
What angle are between directions W (West) and SE (SouthEast) on the compass?
- Cone and the ratio
Rotational cone has a height 28 cm and the ratio of the base surface to lateral surface is 4: 7. Calculate a surface of the base and the lateral surface.
- Right triangle
Calculate the missing side b and interior angles, perimeter and area of a right triangle if a=10 cm and hypotenuse c = 16 cm.
Marie earns 1.8 liters of blueberries for 1.2 hours, Peter 2.6 liters for 1.2 hours. How long have earns together one liter?
From 8 products are 2 scrap. What is the probability that the random pick of 2 products have no defective product?
Calculate how many 25 kg bags of leveling concrete must be purchased if we leveling room 28 m2 to the "height" 12 mm if consumtion is 1.7 kg per square meter and millimeter thickness.
- Cardboard box
We want to make a cardboard box shaped quadrangular prism with rhombic base. Rhombus has a side of 5 cm and 8 cm one diagonal long. The height of the box to be 12 cm. The box will be open at the top. How many square centimeters cardboard we need, if we cal
- Coin and die
Flip a coin and then roll a six-sided die. How many possible combinations are there?
- Triangular pyramid
Calculate the volume and surface area of a regular triangular pyramid whose height is equal to the length of the base edges 10 cm.
- Three workers
Three workers A, B, C have to work on a specific task. Workers A and B completed whole task in 25 days, B together with C for 16 days, A together with C for 10 days. How long it would take to complete the task every one of them alone? How long it would.
- Drunk man
Drunkman has 2.1‰ of alcohol in the blood. How many grams of alcohol has in blood, if he have 6 kg of blood?
What is the weight of concrete cover (lid) to round shape well with a diameter 1.3 m, if the thickness of the cover is 15 cm? 1 m3 of concrete weighs 2190 kg.
The shooter fired to a target from distance 9 m The individual concentric circle of targets have a radius increments 1 cm (25 points) by 1 point. Shot was shifted by 16'(angle degree minutes). How many points should win his shot?
- XY triangle
Determine area of triangle given by line -7x+7y+63=0 and coordinate axes x and y.
- Triangle angles
The angles α, β, γ in triangle ABC are in the ratio 10:5:6. Calculate size of angles.
- Square grid
Square grid consists of a square with sides of length 1 cm. Draw in it at least three different patterns such that each had a content of 6 cm2 and circumference 12 cm and that their sides is in square grid.
- 3y inflation
Price of the medicament rise in the first year by 8%, the second year fell by 4% and in the third year increased by 10%. Calculate the average annual increase in price of the medicament.
- Discounts on rail (ZSSK)
The railway company ZSSK offers a discount of 40% (JUNIOR RAILPLUS EURO