Math practice for 13 year olds - page 343 of 423
Number of problems found: 8460
- Original reduce
If we reduce the unknown number by 469, we get 65% of the original number. What is the original number? - Identical 3452
Two identical cars use 12 l of petrol to cover 150 km. How much gasoline do 25 similar cars use per 1800 km? - Average 3447
The width of the well with the masonry should be 1.8 m. How much will digging a well 16 m deep be paid if an average of 800 CZK is paid from meter cubic? - Shelter 3446
The shelter buys a supply of food for 12 dogs for one week. How many days will this supply last if two more dogs are added to the shelter? - Pyramid in cube
In a cube with an edge 12 dm long, we have an inscribed pyramid with the apex at the center of the cube's upper wall. Calculate the volume and surface area of the pyramid. - The tent
The tent shape of a regular quadrilateral pyramid has a base edge length of a = 2 m and a height of v = 1.8 m. If we have to add 7% of the seams, how many m² of cloth did we need to make the tent? How many m³ of air will be in the tent? - Cube walls
Find the volume and surface area of the cube if the area of one wall is 40 cm². - Five pumps
Three same pumps fill the tank with 50400 liters of diesel in 7 hours. How many liters of diesel will it take in 4 hours if we add two more of the same pumps and pump them the same way? How much more (or less) will they get if we add 2 of the same pumps a - Copper wire
What is the weight of 1000 m copper wire with a diameter of 5 mm when metric density p = 8.8 g/cm³? - Cleaning 3434
During spring cleaning, the removal of scrap iron by truck would take 15 hours. With one tractor, it would take three times as long. In how many hours will the scrap iron be removed if the removal is carried out by a truck and two equally powerful tractor - Aquarium 3432
The aquarium has the shape of a block with a length of 0.7 m and a width of 25 cm. It can hold 56 liters of water. How deep is the aquarium? - Pyramid four sides
A regular tetrahedral pyramid has a body height of 38 cm and a wall height of 42 cm. Calculate the surface area of the pyramid; the result is round to square centimeters. - RT perimeter
The leg of the rectangular triangle is 7 cm shorter than the second leg and 8 cm shorter than the hypotenuse. Calculate the triangle circumference. - trapezium 3428
Given is a trapezoid ABCD with bases AB, CD. Let K be side AB's midpoint, and point L be side CD's midpoint. The area of triangle ALB is 15 cm2, and the area of triangle DKC is 10 cm². Calculate the area of trapezium ABCD. - Subsequent 3427
Find how many strings there are in the first row if there are 44 strings in the eighth row, and in each subsequent row, there are five more strings than in the previous row. - Apples 3424
57 kg of 3q red apples is dried. How many dried apples do we get from 60 kg of fresh apples? - Accepted 3423
The material for 83 masons of the company is enough for 12 days. How many days will this supply be enough for them if the company has accepted six more masons? - Summer camp
Out of the 180 students at a summer camp, 72 signed up for canoeing. Twenty-three students signed up for trekking, and 13 also signed up for canoeing. Use a two-way table to organize the information and answer the following question: Approximately what pe - Quarter 3421
Lukáš was saving for new roller skates. The first month he saved a third of their price, the second month a quarter, the third month half of the rest of the price, and the fourth month €25. How much € did the skates cost? - Ninety-six 3420
Ninety-six soldiers will build a pontoon bridge in 5 hours. How long before the same bridge creates 54 soldiers?
Do you have unsolved math question and you need help? Ask a question, and we will try to solve it. We solve math question.
