Math practice for 13 year olds - page 54 of 351
Number of problems found: 7012
- Pampalini 81604
Pampalini, an animal hunter, told a stranger how he caught a huge crocodile. He claimed that his head was as long as half his tail, and his body was as long as three and a half heads. How long was the crocodile if you know its tail was 4 meters? - Average 81602
A monthly fee of 60 crowns is paid for the phone and 3 crowns for each call. How many calls did we have when one call cost us an average of 4 crowns and 20 pennies? - Perimeter 81600
The radius of the circular bed is 2 m. Around it is an area filled with sand, the border of which is formed by the sides of a square with a length of 5 m and the bed's perimeter. Calculate the volume of the area covered with sand. - Forty-five 81599
Lukas left the Tereza cottage and walked at an average 4 km/h speed. Forty-five minutes later, Jakub followed him on a bicycle from the same cottage. He followed Lukas's route and caught up with him after 20 minutes. What was Jakub's average speed?
- Periodic function
Simplify by using periodicity cos 1125° - Intersection 81594
Given a trapezoid ABCD and the sizes of the interior angles. Angle SDC 32° SAD angle 33° SDA angle 77° Angle CBS 29°, where S is the intersection of the diagonals. What is the size of the angle BSA? - Proportion 81593
Express the ratio. There are 12 boys and 16 girls in the class. a) In what ratio is the number of girls to the number of boys? b) In what proportion is the number of boys to the total number of pupils? - Performance 81586
The performance of three lathes can be expressed by the ratio 3:5:8. The most powerful lathe produces 136 shafts per shift. How many shafts did each of the remaining lathes make per shift? - Deposited 81585
Mr. Investor deposited half of his money in the bank at 5% interest. He invested the other half in bonds with 7% interest. How much money did he invest when his annual profit was CZK 600?
- Distance 81578
The express train leaves place A at 19:20 and arrives in town B at 20:24. The average speed of the express train is 15 m/s. What is the distance between cities A and B? - Downstream 81577
The water in the river has a speed of 4.8 km/h relative to the bank. A boat in still water has a speed of 12.6 km/h. a) What is the boat's speed relative to the shore if it is sailing downstream and upstream of the river? b) What path will the boat travel - Propagation 81568
A cannon fired at a distance of 2720 m from the observer. The sound of the shot was heard by the observer 8 seconds after the flash. Calculate the speed of sound propagation in the air if we assume that the observer saw the flash at the same time as the s - Discounted 81567
A trip to Egypt was discounted by one-third of the price at the last minute. The discount was 5760 CZK. What was the original price of the tour? - Students 81563 Sixth, seventh, and eighth graders took part in the school trip. Sixth graders were 5 more than seventh graders, and eighth graders were 3 less than sixth graders. How many sixth graders were on the trip if there were 73 students in total?
- Calculate 81560
The cone's surface is 75.36 cm, and the radius is 3 cm. Calculate the volume of the cone. - Together 81559
A car drives for an hour on the highway at a speed of 100 km/h, then for half an hour at a speed of 80 km/h, and for another half hour in the field at a speed of 20 km/h. What track did he run together? What is the average speed of the car? - Proportion 81558
Pour 9 dl of dye into 100 liters of water. What will be the proportion of dye in the resulting mixture? Express as a percentage. - Five-quarters 81556
Add one-third to five-eighths and divide the result by the sum of the numbers five-quarters and two-thirds. - Necessary 81554
It is necessary to determine the number whose double is reduced by 15 equals the number 5.
The picture puzzle made of wooden cubes weighs 0.792 kg. One cube has an edge length of 4 cm and a weight of 33 grams. Find out how many cubes make up a puzzle and calculate the wood density in kg/m³.Do you have homework that you need help solving? Ask a question, and we will try to solve it. Solving math problems.
