Math practice for 13 year olds - page 57 of 419
Number of problems found: 8380
- Circumscribed 83152
Given is an isosceles triangle whose base is 8 cm, and the sides are 15 cm long. Calculate the area of the triangle and the radius of the inscribed and circumscribed circle. - Students 83149
There are 30 students in the class. Five had a mark three — other twos and ones. The average grade was 1.9. How many students got mark one? - Braking 83146
A car of mass m=1t moves at a speed v0=54 km/h. What braking force must be exerted to bring the car to a stop in 10 seconds, and how far will the car travel in this time? - Tetrahedron 83144
A container shaped like a rotating cylinder with a base radius of 5 cm is filled with water. If a regular tetrahedron with an edge of 7 cm is immersed in it, how much will the water level in the container rise? - Basketball 83137
In the basketball game, the players threw 37 times, including 2-pointers and 3-pointers, for a total of 82 points. How many were 2 points, and how many were 3 points? - Republican 83136
In the republican calendar (used in France from 1793 to 1805), one full day was divided into 10 hours; each hour had 100 minutes, and each minute had 100 seconds. What time would the clock show at that time when today's clock reads 15:36? - Dimensions of an aquarium
The large aquarium is shaped like a cuboid and has dimensions in the ratio 5: 7: 4. The sum of the lengths of all edges is 96 dm. How many liters of water will be in the aquarium if it is filled to four-fifths? - Skiing and sledding
Behind the pond, the cat Miki is skiing and Bobo is sledding down a 300-meter-long slope. Careful Bobo can go down the slope in one minute. How many km/h faster does Miki go down the hill than Bobo if he is down 20 seconds earlier? - Banknotes 83131
Cashier Samuel had a total of 20 banknotes in the cash register with a total value of 850 euros. They were only €50 and €20 notes. How many of each bill did he have? - Cylinder's 83130
Calculate the cylinder's volume if you know that the ratio of the cylinder's height to the base's radius is 3:2 and the height is 15 dm. - Katy 7
Katy ordered a cylinder-shaped cake with a volume of 15.7 l. It consists of two layers. The volume of the upper layer is 4 times smaller than the volume of the lower layer. The height of both layers is the same and is equal to the radius of the upper laye - Jendo's 83123
Jenda, Milan, and Tomáš have a total of 203 Pokemon cards. Jenda has twice as many cards as Tomáš, and Milan has a quarter of Jendo's number of cards. a) How many cards does Jenda have? b) How many fewer cards do Milan have than Jenda and Tomáš? - Remaining 83116
Ondra was reading a book. On the first day, he read one-tenth. On the second day, he read half of the remainder; on the third day, he read 20% of the new remainder; and on the fourth day, he read the remaining 72 pages. Thus, the book had 72 pages. - Rectangular 83112
The garden is a rectangular trapezoid a=50m, c=30m, d=15m. If we add an 8% loss to the calculated length, how many meters of mesh do we need to fence it? - Approximately 83106
The castle courtyard, with an area of 100 m², is paved with oak cubes with an edge of 8 cm. Approximately 164 bricks were used to pave m². One dm³ of oak wood weighs 0.8 kg. Calculate the weight of all the bricks used to pave the courtyard. - Notebooks 83101
Jana bought 36 notebooks, three times as many with lines as with squares notebooks. Calculate how many lined notebooks she purchased. - Airship
An airship is at a height x above the ground. Pavel watches it from point A at an elevation angle of 18 degrees 26 minutes. At the same time, Peter sees it from a small plane that is currently flying over Pavel at an altitude of 150m. Peter sees the airsh - Solution 83099
There are spiders and flies on the window. They have a total of 38 legs. How many spiders and flies are there if a spider has 8 legs and a fly has 6? Just give one solution. - Arithmetic 83094
There were 31 students in the class, and the arithmetic average weight was 43 kg. Calculate the average weight in the class if a student weighing 91 kg has been added to the class. - Salt solution
The 50% salt solution must be diluted with distilled water to make 20 liters of 35% solution. How many liters of original solution and how many liters of water do we need?
Do you have unsolved math question and you need help? Ask a question, and we will try to solve it. We solve math question.
