Math practice for 13 year olds - page 61 of 351
Number of problems found: 7016
- Quadrilateral 80729
Quadrilateral ABCD has side lengths AB=13cm, CD=3cm, AD=4cm. Angles ACB and ADC are right angles. Calculate the perimeter of quadrilateral ABCD. - Percentage 80721
Calculate what percentage is €37 from €49. - Cube-shaped 80720
Pavel has a cube-shaped aquarium with a volume of 240 liters. Thomas has an aquarium whose all dimensions are half the dimensions of Paul's aquarium. What is the volume of Thomas's aquarium? - Hibernation 80718
The bear weighed 410 kg at the beginning of winter and lost 10 percent during hibernation. He gained 10 percent of his weight from spring to fall. Find out if the bear's weight was greater at the beginning of winter or autumn by what percentage.
- Effectiveness 80711
When testing the effectiveness of an electric cooker with data of 220 V, 1200 W, 1 kg of water at a temperature of 15 degrees Celsius was boiled for 8.5 minutes. Calculate the stove efficiency corresponding to these data - Percentage 80710
Calculate what percentage is 12€ of 60€. - Determine 80705
The bulb is rated 6 V, 0.2 A. Determine the current rating of the bulb. - Automatically 80704
The electric circuit breaker automatically switches off the circuit of the 220 V electrical network at a current of 6 A. Determine the maximum power in the protected circuit. - Resistance 80703 An immersion cooker has a resistance of 30 ohms and is connected to a voltage of 120 V. How much heat is generated in 2 hours?
- Consumption 80702 A current of 500 mA passed through the filament of a light bulb with a resistance of 400 ohms. What is the consumption of a light bulb in 5 hours?
- Resistance 80699 The immersion cooker plate has data 220 V, 300 W. What is the resistance of the heating wire?
- Resistance 80698 The electric iron plate has written 220 V, 1200 W. What is the resistance of the heating wire?
- Crossbars 80697
Calculate the length of the middle crossbars in an isosceles triangle if the length of the arm is 52mm and the base height is 48mm - Follows 80693
A train travels at a speed of 50 km/h from city A. In 15 minutes, a second train follows him at 20 m/s. We are sitting on the first train. When will the second train catch up with the first?
- Single-digit 80674
There are cows, ducks, and geese on the farm. They have a total of 126 legs. Ducks are 3 more than houses. And there are 20 cows. If we count all the animals, we have to divide them by the number three, and we should get a single-digit number. - Average 80654
On average, 100 liters of milk make 16 liters of cream, and 100 liters of cream make 20 liters of butter. How many liters of milk do we need for 100 liters of butter? - Grandchildren 80639
The average age of the grandfather, grandmother, and their five grandchildren is 26 years. The average age of the grandchildren themselves is 7 years. Grandma is a year younger than grandpa. How old is grandma? - Calculate 80636
Calculate the distance of a chord 19 cm long from the center of a circle with a diameter of 28 cm. - Two-thirds 80635
The car traveled the first third of the track with a constant speed of v1, the next two-thirds of the way at a constant speed of v2=72km/h, and the average speed of v=36km/h. Find v1.
Half a kg of coffee costs CZK 124. Calculate how many crowns you will pay for 3/4 kg of this coffee.Do you have unsolved problem that you need help? Ask a question, and we will try to solve it. Solving math problems.
