Math practice for 13 year olds - page 71 of 434
Number of problems found: 8667
- Rectangle's 81776
The length of the rectangle is 5 cm greater than its width. Determine the rectangle's dimensions if you know that its perimeter is 22 cm.
- Friends 81769
Four guys would finish washing cars at a gas station in 4 hours. After one hour, two more friends come to help them. How long will it take to finish the car wash?
- Machine 81767
Four lathes machine 32 parts in 1 hour. How many parts does 1 turner machine have in 2 hours?
- Divided 81763
Petr divided the 32 playing cards into two piles. He found that one had three times as many cards as the other. How many cards were in each pile?
- Diameter of a drum
Winding drum length 180mm, initial diameter 60mm. Using a 6mm rope with a length of 50m, what will be the diameter of the wound drum with the rope?
- Cylindrical 81748
The hydrostatic pressure at the bottom of a cylindrical water container is 10 kPa. The bottom has an area of 0.25m². How much pressure does the water exert on the bottom?
- Represents 81745
2.5 cm on the map represents 6.25 km in reality. Set the scale of the map.
- ELECTRICAL 81742
A cooker connected to a 40 V voltage source draws a current of 0.5 A. DOES THE SIZE OF THE ELECTRICAL WORK DETERMINE WHICH COOKER DOES IN 3 MINUTES?
- Pupils - class
There are 28 pupils in the class. The ratio of boys to girls is 3:5. Find the number of girls.
- Harvested 81719
Eight hop pickers harvest in 24 days. How many more pickers must be hired if the hops need to be harvested in 16 days?
- Triangle - perimeter
The perimeter of the triangle is 110 cm. Side a is 6 cm longer than side b and 8 cm shorter than side c. Determine the lengths of the sides of the triangle.
- Together 81701
The sisters Pavel and Petra are 29 years old together. Pavla is 3 years younger than Petra. HOW old is Pavle? Thank you very much.
- Advantageous 81698
Mr. Rezek wants to rent an Opel Corsa car for one day. He can choose from two rental tariffs: Tariff 1: Daily flat rate of CZK 1,400. Tariff 2: Daily rental 360 CZK plus 4.50 CZK for each kilometer driven. For what number of kilometers driven is it more f
- Basement 81681
After the flood, the Nováks would pump water out of the basement with one pump in 120 minutes, the second in 300 minutes, and the third in 600 minutes. How many minutes will it take them to pump the water out of the basement if they use all the pumps at o
- Probability 81679
What is the probability that a roll of three dice will result in a number less than 7?
- Probability 81678
What is the probability of guessing a PIN code (4 numbers) if it contains only even numbers?
- Dimensions - crate
A wooden crate with dimensions d=3m, e=4m, and f=3m was placed in a transport container with dimensions a=10 m, b=4m, and c=3m. What is the maximum length of a straight, rigid rod of negligible diameter that can still be placed in the container in this si
- Centimeters 81669
Eight centimeters on the map represent two kilometers in reality. Determine the scale of this map.
- Conservationists 81665
Conservationists cleaned the stream in three days. On the first day, they cleared one-third of the stream. On the second day, one-third of the remaining portion of the stream, and on the third day, they cleared the remaining 8 km of the stream. How long i
- Apartment 81654
A woman cleans an apartment in 8 hours and a man in 10 hours. How many hours will they clean together?
Do you have unsolved problem that you need help? Ask a question, and we will try to solve it. Solving math problems.