Examples for 8th grade - page 78

Plum
On the platter are plum. How many were there if its have to be able to share equally among 8,10 and 12 children?
Class 9A
On the final certificate have one quarter of the class 9A mark "C" of mathematics, seventh mark "C" from the Czech language and two students failed in chemistry. How many students attend class 9A?
Three figures - numbers
The sum of three numbers, if each is 10% larger than the previous one, is 662. Determine the figures.
Greenhouse
Garden plastic greenhouse is shaped half cylinder with a diameter of 6 m and base length 20 m. At least how many m² of plastic is need to its cover?
Pumps
Five pumps pumped 1,800 hl of water for 3 hours. How many hectoliters of water pump same two powerful pumps for six hours?
Line segment
Cut a line segment of 15 cm into two line segments so that their lengths are in ratio 2:1. What length will each have?
Sale off 2
A pair of of blues jeans went on sale. After a 30% reduction the pants cost $35. How much did the jeans cost before the price reduction?
Candy
The price for 1kg of more expensive candy is 125 CZK. The price for 1kg of cheaper candy is 100 CZK. We make two different blends of candy. And now. The second blend contains 2kg of more expensive candy and several kg of cheaper candy. The price per 1 kg o
Family
Mom is 39 years old. Karl is eight years and Paul 4 years. For many years mother would old just like two children together?
Four ropes
TV transmitter is anchored at a height of 44 meters by four ropes. Each rope is attached at a distance of 55 meters from the heel of the TV transmitter. Calculate how many meters of rope were used in the construction of the transmitter. At each attachment.
Image scale
The actual image dimensions are 60 cm x 80cm and has a reduced size 3 cm x 4 cm. At what scale the image was reduced?
Trees - orchard
The 3/5 trees are apple trees and 1/3 of the trees are cherries. The remaining 5 trees are pear trees. How many trees are in the orchard.
Contestants
In the competition it was possible to get 0-5 points. In fact, 5 contestants of the 15 best contestants has earned 5 points or 4 points (which have won 10 contestants). The number of contestants who earned 3 points was the same as the number of contestan
Cableway
Cableway has a length of 1800 m. The horizontal distance between the upper and lower cable car station is 1600 m. Calculate how much meters altitude is higher upper station than the base station.
Cost reduction
Two MP3 players whose price was equal to originally have been discounted the first by 20%, the second by 35%. After the price reduction was the difference in their prices 750, - CZK. What was the original price of each of the two players?
Family parcels
In father will he divided the land so that the older son had three bigger part than younger son. Later elder son gave 2.5 ha field to younger and they had both the same. Determine the area of family parcel.
Cuboid easy
The cuboid has the dimensions a = 12 cm, b = 9 cm, c = 36 cm. Calculate the length of the body diagonal of the cuboid.
Cruise liner
Cruise liner runs along the river between points A and B. The journey downstream takes 40 minutes 1 hour upriver. The flow rate of the river is 3 km/h. What is the speed of cruise liner?
Sugar 9
150 kg of sugar beet yields 24 kg of sugar. From how many tons of sugar beet can be obtained three tons of sugar?
Two numbers
$fractal_6$ The sum of the two numbers is 1. Find both numbers if you know that half of the first is equal to one seventh of the second number.

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