Equation + expression of a variable from the formula - math problems

  1. Circle and square
    square_axes An ABCD square with a side length of 100 mm is given. Calculate the radius of the circle that passes through the vertices B, C and the center of the side AD.
  2. The circumference
    rectangle The circumference and width of the rectangle are in a ratio of 5: 1. its area is 216cm2. What is its length?
  3. Side lengths
    triangles_1 In the triangle ABC, the height to the side a is 6cm. The height to side b is equal to 9 cm. Side "a" is 4 cm longer than side "b". Calculate the side lengths a, b.
  4. The number 72
    percent_2 The number 72 increase by 25%. By how much % will you have to reduce the number you created to get the number 72 again?
  5. The farmer
    cow The farmer calculated that the supply of fodder for his 20 cows was enough for 60 days. He decided to sell 2 cows and a third of the feed. How long will the feed for the rest of the peasant's herd last?
  6. In a
    triangles_1 In a triangle, the aspect ratio a: c is 3: 2 and a: b 5: 4. The perimeter of the triangle is 74cm. Calculate the lengths of the individual sides.
  7. Library
    books_1 New books were purchased for the library. Five-eighths were professional books, one-fifth were encyclopedias, and 231 books were dictionaries. How many professional books were there?
  8. Double price reduction
    tv The price of TV has been reduced twice. First by 15% and later by another 10% of the reduced price. After this double price reduction, the TV was sold for 8,874 crowns. What was the original price of the TV?
  9. A map
    land_1 A map with a scale of 1: 5,000 shows a rectangular field with an area of 18 ha. The length of the field is three times its width. The area of the field on the map is 72 cm square. What is the actual length and width of the field?
  10. An equilateral
    rs_triangle2 An equilateral triangle is inscribed in a square of side 1 unit long so that it has one common vertex with the square. What is the area of the inscribed triangle?
  11. Hectares of forest
    stromy 12 workers plant 24 ha of forest in 6 days. In how many days will 15 people and 12 people plant the same area?
  12. Using
    runners Using one of the following forms x+p=q or px=q write an to represent these problems using x as the unknown variable Larry ran 7 more miles than Barry in a month, if Larry ran 20 miles how many did Barry run? please help its due tomorrow
  13. Block or cuboid
    cuboid The wall diagonals of the block have sizes of √29cm, √34cm, √13cm. Calculate the surface and volume of the block.
  14. Cuboid and ratio
    cuboid_2 Find the dimensions of a cuboid having a volume of 810 cm3 if the lengths of its edges coming from the same vertex are in ratio 2: 3: 5
  15. Volume of wood
    wood Every year, at the same time, an increase in the volume of wood in the forest is measured. The increase is regularly p% compared to the previous year. If in 10 years the volume of wood has increased by 10%, what is the number p?
  16. Growth of wood
    wood The annual growth of wood in the forest is estimated at 2%. In how many years will make the forest volume double?
  17. Mortage hypo loan
    hypo The Jonáš family decided to buy an older apartment, which cost EUR 30,000. They found EUR 17,000 and took the loan with the bank for the remaining amount. What interest did they receive if they repay this amount for 15 years at EUR 120 per month?
  18. Water container
    cubes2 The cube-shaped container is filled to two-thirds of its height. If we pour 18 liters, it will be filled to three-fifths of the height. What is the volume of the whole container?
  19. The bridge
    bridge2 A vehicle weighing 5,800 kg passes 41 km/h on an arched bridge with a radius of curvature of 62 m. What force is pushing the car onto the bridge as it passes through the center? What is the maximum speed it can cross over the center of the bridge so that
  20. Same force
    wood The trunk of 5m length and 95 kilograms has a center of gravity 2m from the thicker end. The tribe is carried by two men, one at the thicker end. At what distance does the trunk carry a man from the other end to make the same force on it?

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