Math practice for 13 year olds - page 322 of 436
Number of problems found: 8719
- Regular n-gon
Which regular polygon has a radius of circumscribed circle r = 10 cm and the radius of inscribed circle p = 9.962 cm? - Harvesters 4498
The first combine harvester will harvest the fields in 12 hours, and the second combine harvester in 8 hours. How long does it take for the same harvester to harvest the 3rd combine if all three harvesters harvest together in 2 hours? - Average speed
When the bus stops at a bus stop, the average speed is 45 km/h. It would drive at 54 km/h if it did not stop. How many minutes of every hour does it spend at stops? - Obtained 4484
25% oil is obtained from one flaxseed. From how many kg of flax seeds is 1.5 kg of oil obtained?
- Aircraft 4480
Two planes take off simultaneously from airports A and B, fly towards each other, and meet in 20 minutes. The distance between the airports is 220 km, and the average speed of the aircraft flying from airport A is 60 km/h more than the average speed of th - Simultaneously 4479
A worker would fill the tank with one inlet in 36 minutes, the other in 45 minutes. How long will it take to fill the tank if the water flows through the first inlet for 9 minutes and then both simultaneously? - Expensive 4478
Five liters of white wine and six liters of red wine cost 432 CZK. One liter of red wine is CZK 6, which is more expensive than one liter of white wine. Thus, we pay CZK 6 for one liter of white wine and CZK 6 for one liter of red wine. - Diagonals of a rhombus
One of the diagonals of a rhombus is twice the other. If the sum of the lengths of the diagonals is 24, find the area of the rhombus. - Father and sons
After 15 years, the father will have as many years as his two sons together now. There is a six-year difference between the brothers, and the older one celebrated fifty years three years ago. How old is their father now?
- Pharmacy
The pharmacy adds 3 liters of 95 percent alcohol and 5 liters of 38.04 percent alcohol. How much percent alcohol did the pharmacy get? - Temperature 4474
Mom is going to wash by hand in water that should be at 40°C. The tub already has 10 liters of water at a temperature of 12.3°C and can still hold 5 liters. What temperature should the water be allowed to be? - Equation: 4472
Solve the equation: x!: 5 = 1008 The solution to the equation is a natural number. - Security
The safe's security code is set with three dials. The first dial has five different letters, the second dial has the numbers 0 to 4, and the third dial has the numbers 5 to 9. One code can be set in approximately 1 second. How should the alarm be timed so - Passenger 4468
A truck left Beroun at 7 o'clock in the direction of Prague on the highway in the fog. In 20 minutes after that, a car drove by at the same place and along the same route at a 27 km/h higher speed. The passenger car overtook the truck after another twenty
- Time gone The Square of Richard's age equals the age of his mother. When he is two times older, his mom will be seven times older than him. Thus, Richard and his mom are seven times older.
- Right triangle eq2
The hypotenuse of a right triangle is 9 cm longer than one leg and 8 cm longer than the second leg. Determine the circumference and area of a triangle. - Minutes 4465
Peter and Karel live at the same address. Peter will drive to the stadium in 30 minutes and Karel in 40 minutes. If Karel goes 5 minutes early, where will Peter catch up? - Sheriff 4462
The cowboy will give the sheriff two bags of oats, and the sheriff will have 2x more bags than the cowboy. If the sheriff gives two bags of oats to the cowboy, they will both have the same. How many bags does each have? - Arrangements 4459
There are 4 classrooms on the ground floor of the school building, which are numbered 1,2,3,4. First-year students A, B, C, and D will be placed in these classrooms. Write all possible class arrangements and their number. Thank you
Calculate how many trees are in an orchard if you know that 5/12 orchards consist of apple trees, 1/6 plums, and 1/60 walnuts. The remaining 30 trees are pear trees.Do you have homework that you need help solving? Ask a question, and we will try to solve it. Solving math problems.
