Maths practice for 14 year olds - page 52 of 376
Number of problems found: 7503
- Current thermal energy
How long will it take for a current of 8A in a resistance of 30 ohms to develop thermal energy of 3 MJ if the efficiency of converting electrical energy into heat is 90%? - Number ratio subtraction
I think two numbers. Their ratio is 5:7. If 3 is subtracted from the first and 7 from the second, then the ratio is 6:7. What number was I thinking? - Cube triangle volume
In the cube ABCDEFGH, the area of triangle ABK is √20 cm². How much cm² is the volume of ABGH in a cube if you know that K is the midpoint of edge CG? - Triangle area side
Calculate the area of an isosceles triangle ABC with a base of 10 cm and a side of 7 cm. Sketch a picture. - Trapezoid perimeter base
An isosceles trapezoid has one base twice as short as the other. Its area is 42 cm², and its height is 4 cm. Calculate its circumference if you know that the arm is 5.3 cm long. - Prism pyramid ratio
For the volumes of a perpendicular prism and a pyramid with the same base and height: A) the volumes are equal B) the volume of a pyramid is three times smaller than the volume of a prism C) the ratio of the volumes of the prism and the pyramid is 1:3 D) - Castle tour time
The tour of the castle takes 72 minutes, and the tour of the cellar took half the time compared to the tour of the interiors. In the garden, visitors then spent 20% of the time they were inside (in the cellar and the castle). How long did the tour of the - Peter example solving
Peter solves 40 examples. For a correctly solved example, he receives CZK 5 from his mother. For example, in a poorly solved case, he will pay 20 CZK to his mother. After solving all the examples, he had CZK 25 more than when he started counting. How many - Banknote payment count
CZK 8,000 was paid out in fifty pieces of banknotes in denominations of CZK 100 and CZK 200. How many were there? - Triangle height line
In the right triangle KLM, the hypotenuse l = 9 cm and the perpendicular k = 6 cm. Calculate the size of the height vl and the line tk. - Triangle interior angles Calculate the interior angles of the triangle. The angle alpha is 16° greater than beta, and the angle gamma is 17° less than alpha.
- Glass cocktail level
The cone-shaped glass has a volume of 2.5 dl and a diameter of 13 cm. How much cocktail is left in the glass if the level only reaches half the height of the glass? - Angular velocity Determine the difference in angular velocities of the clock hands. [rad/s] ω of clock hands =? ω minute hands =? ω second hands =?
- Diagonal of a cube
Calculate the volume of a cube with a wall diagonal of u = 20 cm. - Rectangle perimeter ratio
The sides of the rectangle are in the ratio of 5 : 8. Its perimeter measures 208 cm. Determine the area of this rectangle. - Stipend double increase
University students increased their stipend by 20% and then again by 10%. Now he gets 99 euros. What was his original scholarship? - Flag color combinations
How many 4 colored flags can be made from 5 colors so that each flag consists of three different colors? - Motorcycle acceleration time
Motorcyclist Arnošt begins to move on his motorcycle in a uniformly accelerated motion with an acceleration of 1.6 m/s². At what time will it reach a speed of 50 km/h? What distance will it travel at this time? - Number sum puzzle I think of three numbers. When I add them, I get 15. When I subtract the third number from the sum of the first two numbers, I get 10. When I subtract the second number from the sum of the first and third numbers, I get 8. What number do I think?
- Class boy girl
If 3 boys were added to the eighth grade, 50% of the class would be boys. If, on the other hand, 3 girls were added, they would make up 7/12 classes. How many children are there in the class?
Do you have homework that you need help solving? Ask a question, and we will try to solve it. Solving math problems.
