Math practice for 13 year olds - page 372 of 424
Number of problems found: 8477
- Vinegar
What percentage of vinegar do we get if we mix 1 dm³ of eight percent vinegar with 1.5 dm³ of six percent vinegar? - 12 Moons
Good Marry came to ask the twelve Moons for strawberries. All twelve Moons would have picked 1200 strawberries in 20 minutes. However, in 5 minutes the lazy holiday Moons - July and August stopped picking. How many minutes in total will it take collect st - Two numbers
Determine the numbers x and y, so x + y = 8 is true, and the numbers are in the ratio of 4:5. - Three numbers
Find three numbers so that the second number is four times greater than the first and the third is lower by five than the second number. Their sum is 67. - Concentration
We want to dilute 0.5 litres of 8% vinegar to a concentration of 0.20%. How many litres of water must we add? - Water tank 2
The water tank cuboid is 12 meters long and 6.5 meters wide, and 1.2 meters high. How many hectoliters are in the tank when it is filled to 89%? - Brackets
Place one pair of brackets in the expression 20-16 + 10 - 4 - 2 so that the result will be 0. - Password dalibor
Camilla wants to change the password daliborZ by a) two consonants exchanged between themselves, b) changes one little vowel to such same great vowel c) makes these two changes. How many opportunities do you have a choice? - Image scale
The actual image dimensions are 60 cm x 80 cm and have a reduced size of 3 cm x 4 cm. At what scale was the image reduced? - Trees
Loggers wanted to seed more than 700 and less than 800 trees. If they seed in rows of 37, leave them eight trees. If they seed in rows of 43, leave the 11 trees. How many trees must seed? - Apples 2
On the first day fell one-third, on the second quarter of the rest and on the tree remained 45 apples? How many apples were originally on the tree? - Trams
Tram no. 3,7,10,11 rode together from the depot at 5 AM. Tram No. 3 returns after 2 hours, tram No. 7 an hour and a half, no. 10 in 45 minutes, and no. 11 in 30 minutes. For how many minutes and when do these trams meet again? - Triangular pyramid
Determine the volume and surface area of a regular triangular pyramid having a base edge a=20 cm and a lateral edge b = 35 cm. - Aquarium 6
How high is the water level in the aquarium with a rectangular base of 40cm and 50cm if it is filled with 0,65hl of water? - Aquarium volume
The aquarium has a cuboid shape and dimensions a = 0.3 m, b = 0.85 m, c =?, V = ?. What volume has a body if, after dipping into the aquarium water level rises by 28 mm? - Water pool
A pool with a volume of 990 hl is completely filled if water flows from one tap for 8 hours and from a second tap for 6 hours. The first tap delivers 10 hl more per hour than the second. How many hl per hour does each tap deliver? - Principal and interest
Peter put € 270 principal into the bank, and at the end of the year, the account was € 282. To what annual interest rate did Peter deposit money in the bank? - Sales off
Goods are worth € 87, and the price of goods fell by two weeks in a row by 10%. How much percent decreased overall? - Great Wall of China
The Great Wall of China is 8880 km long. Historically valuable, however, is only 30% of its length. What amount of insurance pays the People's Republic of China a month for this monument if the insurance company charges $ 10 per year per kilometer of hist - Diamond
Calculate the length of the two diagonals of the diamond if: a = 13 cm v = 12 cm
Do you have homework that you need help solving? Ask a question, and we will try to solve it. Solving math problems.
