Math practice for 13 year olds - page 260 of 428
Number of problems found: 8554
- Construction Material
A smaller car would bring 40 times the material needed for construction, and a larger car 30 times. When the first and second cars had made 12 trips, the smaller car was recalled, and the larger one was to bring the remaining material. How many more roads - Two Inlets Fill Time
The water tank is filled with the first inflow in one hour and 10 minutes and the second in 60 minutes. How many minutes will the tank be half-filled with both inlets if the second outlet is opened 12 minutes later? - Computer task time
In a computer center, one computer would work 12 hours to solve a task, and another, more powerful, would solve the same task for 10.5 hours. If both computers work together, the calculation time would be reduced for a certain period. Calculate how long i - The factory
The factory z can complete an order in 12 days, and factory p can complete it in 18 days. How many days does an order complete when the first two days work only the factory z and then both factories? - Two Tractors Field Time
One tractor driver would mow the field in 15 hours. Another tractor driver would do the same job in 12 hours. How long will it take them to do the work together if the latter starts plowing two hours later than the former? - Water reservoir
One drain hole emptied the water from the tank for 20 hours, with the second drain for 30 hours. How long will the water drain from this tank if we open two drains simultaneously? - Three-digit numbers
Use the number 4,5,8,9 to write all three-digit numbers without repetition. How many such numbers are there? - Beds
At the summer camp, there are 41 chalets. Some rooms are 3 beds, some 4-beds. How many campers from 140 are living in 3-bed? - Uncle Nephew Age Puzzle
Uncle Josef is three times as old as Michal. Twelve years ago, Josef was nine times older than Michal. How old are they now? - Land division calculation
The king divided part of his lands between his three sons. To the first, he gave one-fifth. To the second, he gave 40 ha less than the first, and to the third, he gave 30% of the whole. Write down what part of the land was left to the king. Calculation us - Brother sister age
The brother and sister will be a total of 73 years old. At present, a sister is one-tenths older than her brother. How old are they now? - Two Workshops Joint Work
In one workshop, they will do the given work in 15 days; in another workshop, where more members work, they will do the given work in 10 days. After three days of joint work, only the larger workshop continued the assigned work. In how many days will he f - Rice flour cost
Marta bought 10 kg of rice and 25 kg of flour for 40 euros. A kilogram of flour and a kilogram of rice together cost 1.80 euros. How much does 1 kg of each type of goods cost? - Hockey stadium fans
At the hockey match, the stadium was full at the beginning. After the first period, 20% of the fans left; after the second period, one-sixth of the remaining fans left. How many fans were in the stadium at the start of the match if 700 stayed until the en - Pavel Karel age
Paul's age is 60% of Karel's age. In 15 years, Paul's age will equal 80% of Karel's age. How old is Pavel? - Selling price
Find the selling price. Cost to store: $50 Markup: 10% - Odd/even number
Pick any number. If that number is even, divide it by 2. If it's odd, multiply it by three and add one. Now, repeat the process with your new number. If you keep going, you'll eventually end up at one every time. Prove. - Digit puzzle
Four different digits were on the four cards, one of which was zero. Vojta composed the largest four-digit number from the cards, and Martin the smallest four-digit number. Adam wrote the difference between Vojtov's and Martin's numbers on the board. Then - Flowers Bouquet Colors Count
Two-quarters of the flowers are red. One-third is yellow, and three flowers are blue. The bouquet has a total of __ flowers. - Waste Paper Collection Comparison
Ema collected 770 kg of waste paper during the school year, while her friend Patrik collected 15% less. During the following school year, Ema collected exactly as much as Patrik did last year, but Patrik managed to collect 15% more than Eme. Which one col
Do you have homework that you need help solving? Ask a question, and we will try to solve it. Solving math problems.
