Maths practice for 14 year olds - page 294 of 361

Number of problems found: 7208

Cylinder surface
The surface of the cylinder with a base diameter of 20 cm and a height of 0.3 m is approximate.
Prism - box
The prism's base is a rectangle with a side of 7.5 cm and 12.5 cm diagonal. The volume of the prism is V = 0.9 dm³. Calculate the surface of the prism.
Oil cans
Workers rolled the oil into 115 two-liter and three-liter cans from a full three-hectolitre barrel. How many cans were there?
Cylinder
A 1-meter diameter cylinder is 1413 liters of water, which is 60% of the cylinder. Calculate the cylinder height in meters, do not write the units. Please the resulting value round and write it as an integer.
Triangle perimeter
The right triangle has squares in the ratio of 5:12, and the circumscribed circle diameter is 26 cm. Determine its perimeter.
Gardens
I have a garden in the shape of a square with a side length of 0.02 kilometers. The neighbor has a large garden, and we share one side of the garden. I bought from a neighbor's garden, and my garden area increased to 5 ares. I. By how many acres I purchas
Siblings
Three siblings had saved up a total of 1,274 CZK. Peter had saved up to 15% more than George and Hannah, 10% less than Peter. How much money did they save for each one of them?
Electricity consumption - Filip
Last year Filip was writing a long school paper. As a great conservationist of nature, however, he was unable to decide which is more ecological - to write the paper on a computer, or to write the paper by hand. Filip found out that: the paper written on
Costume
Denisa is preparing for a goldsmith's costume carnival. During the preparations, she thought she would let her hair wipe instead - she would apply a 5 μm thick layer of gold to each hair. How much gold would Denisa need? Assume that all hundred thousand D
Concentration
How many grams of 65% and 50% acid are to be mixed to give 240 g of acid with a concentration of 60%?
Acid solution
By adding 250 grams of a 96% sulfuric acid solution to its 3% solution, we changed its initial concentration to 25%. How many grams of 3% of the acid were used for dilution?
Product of three
The product of 3 numbers is 42. The first is 1.5 times larger than the second number, and the third is 3.5 times larger than the second number. What numbers are these?
Water mixing
Find how many liters of water at 80 °C and 20 °C need to mix to get 30 liters at 60 °C.
Tree storm
In the orchard, there were 46 more apple trees than pears. The storm upset a quarter of apple trees and seven pears; however, there were still 80 trees left. How many were apple trees, and how many pears were in the garden?
Apple baskets
How many apples are in the fifth and eighth baskets if there are five apples in the first and 11 more apples in the next than in the previous one?
Water mixing - tub
The tank has water with a volume of 300 liters and a temperature of 10 °C. Add water at a temperature of 90 °C until a temperature of 30 °C is reached. How many liters of warmer water do I need to add?
Concrete block
Determine the volume of the concrete block whose one edge of the base is 3 meters long, the body diagonal is 13 meters, and the height is 12 meters.
Distilled water
Seawater contains 5% salt. How much distilled water should be poured into 40 kg of seawater so that the salt content is 2%? How many kilograms of 2% of seawater do we get?
Number difference
The difference between the two numbers is 4/3. If you know that the first number is 50% larger than the second number, specify both numbers.
Water temperatures
To 25 liters of water at 50 °C, we add 15 liters of water at a different temperature. How many °C should the water be colder than 50 °C so that 40 liters of the water obtained has a temperature of 42.5 °C?

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