# Unit conversion - 7th grade (12y) - math problems

#### Number of problems found: 359

• Coke and coal 20.1 tons of coke is produced from 30 tons of black coal. How much coke is made from 1 kilogram of coal?
• Quarter of an hour If the clock showed a quarter of an hour more, it would be 10 minutes to 10 hours. How many hours do they show?
• Hectares Determine the area of the rectangular land (in ha), which has dimensions of 3 cm and 4.5 cm on the plan with a scale of 1: 40,000.
• Concrete hatch The concrete hatch for a round well has a diameter of 1300 mm and a thickness of 80 mm. Determine its weight in kg if the density of the concrete is 2545 kg/m3
• Volume per time How long does fill take for a pump with a volume flow of 200 l per minute fill a cube-shaped tank up to 75% of its height if the length of the cube edge is 4 m?
• Nautical miles How many nautical miles do they sail if the route is shown on a 1:25 000 scale map with a 7.4 cm long line?
• Flowerpot The block-shaped flowerpot has external dimensions: length 1.25 m, width 10 cm and height 11 cm. The thickness of the boards from which it is made is 0.8 cm. How many liters of soil is needed to fill it 1 cm below the top edge? What surface do we have to
• Nutballs The dough for nutballs contains, among other things, two basic raw materials: flour and nuts in a ratio of 2:1. How much flour and how many nuts are needed for 1 kg of dough if "other" is 100g?
• Chestnuts Three divisions of nature protectors participated in the collection of chestnut trees.1. the division harvested 1250 kg, the 2nd division by a fifth more than the 1st division and the 3rd division by a sixth more than the second division. How many tons of
• Cylindrical tank 9.6 hl of water is poured into a cylindrical tank with a bottom diameter of 1.2 m. What height in centimeters does the water reach?
• Marlon Marlon drew a scale drawing of a summer camp. In real life, the sand volleyball court is 8 meters wide. It is 4 centimeters wide in the drawing. What is the drawing's scale factor? Simplify your answer and write it as a ratio, using a colon.
• Aquarium How many liters of water can fit in an aquarium measuring 30, 15 and 20 cm?
• Aquarium height How high does the water in the aquarium reach, if there are 36 liters of water in it? The length of the aquarium is 60 cm and the width is 4 dm.
• Weight The kilogram weight has a volume of 116 ml. From which material is it probably made? Use substance density tables, e. G. mathematical-physical-chemical tables.
• Brick wall What is the weight of a solid brick wall that is 30 cm wide, 4 m long and 2 m high? The density of the brick is 1500 kg per cubic meter.
• Tram stop The blue tram stops every 12 minutes, the red one 8 minutes. At 8 o'clock they left the stop together. How many times do they meet at a stop before 11 am?
• Largest wall Find the content of the largest wall of a prism with the base of a rectangle which has a height of 4 dm, side c = 5 cm, and side b = 6 cm.
• Unknown metal The prism made of unknown metal has dimensions of 3 cm by 3 cm by 5 cm and a weight of 121 g. What metal is it? Write its chemical symbol.
• AL wire What is the weight of an aluminum wire 250 m long with a diameter of 2 mm, if the density of aluminum is p = 2700 kg/m cubic. Determine to the nearest gram.
• The plan The plan of the housing estate is in three scales 1: 5000,1: 10000,1: 15000. The distance between two points on a plan with a scale of 1: 10000 is 12 cm. What is this distance on the other two plans? What is this distance?

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