Math practice for 13 year olds - page 55 of 351
Number of problems found: 7012
- Single-digit 81549
Calculate the sum of the squares of single-digit natural numbers less than 6 - Wreaths 81547
Eva paid €8.4 for three wreaths and five creams. Jana paid €15.6 for 9 wreaths and 7 creams. How many crowns will Jan pay for one wreath and one cream? - Three ratios
Calculate x in terms of: x:7=6:4 1/2:x=5:3/4 4:3=8:x - Percentage 81539
Over five years, the number of pupils in the school decreased from 455 to 335. By what percentage did the number of pupils decrease?
- Subsequently 81532
Dresses that initially cost 100 € after a double discount of 10% subsequently increased in price by 20%. How much did they cost? - Children 81526
There are 32 children in the class. If there were three more boys and one less girl, there would be an equal number of girls and boys in the class. How many boys are there in the class? - Glasses 81522
5 out of 32 plates and 2 out of 20 glasses were broken at the party. What is the ratio of plates to glasses now? - Together 81521
Pavel and Vojta were planting trees at the forestry brigade. Pavel planted two more trees than Vojta in a six-hour shift. Together, they planted 156 saplings in three such shifts. How many saplings did Pavel and Vojta plant during the brigade? - Diamond-shaped 81516
How many diamond-shaped tiles with a side of 25 cm and a height of 20 cm are needed to pave a rectangular courtyard with sides of 30 m and 28 m if the joints represent 1/20 of the area?
- Decorations 81510
The glass Christmas decorations have the shape of a ball with a diameter of 8 cm. In a small family business, they produce 50,000 pieces a year. The entire surface of these balls is covered with glitter. 400 g of glitter is needed to cover an area of 1 m² - Body's 81509
What was the body's mass when it moved along a path of 70 dm and did 1.4 kJ of work? - Resistance 81503
What is the value of the resistance of the rectifier diode in the forward direction if the current IF = 5 A flows through it and the voltage between the anode UF = 820 mV? - Resistor 81502
How big a series resistor do we need to connect to the LED if a voltage drop of 3.2 V is to be created on it and a current of 16 mA flows through the diode? We want to connect the diode to a voltage of 5V. - Threefold 81491
Find a number whose fivefold is 8 greater than threefold.
- Indistinguishable 81481
How many ways can a tower of five yellow and four blue cubes be built so that each yellow cube is adjacent to at least one other yellow cube? Yellow dice are indistinguishable, and so are blue dice. - Archaeologists 81478
Archaeologists need to find out the size of the vessel if the sherd found was in the shape of a circular section with a length of 12 cm and a height of 3 cm. What is the area of this section? - Quadrilateral calc The square ABCD is given. The midpoint of AB is E, the midpoint of BC is F, CD is G, and the midpoint of DA is H. Join AF, BG, CH, and DE. Inside the square (approximately in the middle), the intersections of these line segments form a quadrilateral. Calc
- Identical loaves of bread
If the clerk at the buffet bought 15 identical loaves of bread, she would have 5 euros left in her wallet. If she bought 3 loaves of bread less, she would have 8.60 euros left. How many euros did she have in her wallet? - Times 81462
5 to -11 times 5 to -7/5 to zero times 5 to -15 minus ( -5 ) to -2
Two cars started from the right-angled intersection of two roads. The first at a speed of 80 km/h and the second at a speed of 60 km/h. How fast are they moving away from each other?Do you have unsolved problem that you need help? Ask a question, and we will try to solve it. Solving math problems.
