Expression of a variable from formula - math word problems - page 14

  1. Square
    ctverec_1 Danov's father has a square of 65.25 milligram square of wire with a diagonal. How will the square be big when one mm weighs 7 mg?
  2. Cylinder
    cylinder_6 In a 1-meter diameter cylinder is 1413 liters of water, which is 60% of the cylinder. Calculate the cylinder height in meters, do not write the units. The resulting value round and write as an integer.
  3. Surface of cuboid
    kvader11_9 Find the surface of the cuboid if its volume is 52.8 cm3 and the length of its two edges is 2 cm and 6 cm.
  4. Alcohol
    metaxa How many cubic centimeters of 96% alcohol is needed to obtain 0.75 liter of 40% alcohol?
  5. Unknown number 4
    ninth I think number. When I divided its square root by its 1/9, I get a number 1. What number am I thinking?
  6. Trench
    lichobeznik_4 The trench is a four-sided prism. The cross section has a trapezoidal shape with basements of 4m and 6m, the length of the trench is 30m. What is the depth of the trench if we dig 60,000 l of soil.
  7. Rectangle
    obdlznik The length of the rectangle is 12 cm greater than 3 times its width. What dimensions and area this rectangle has if ts circumference is 104 cm.
  8. Sale off
    percents2_1 Product cost 95 euros before sale off. After sale off cost 74 euros and 10 cents. About what percentage of produt became cheaper?
  9. Body diagonal
    kvader11_1 The cuboid has a volume of 32 cm3. Its side surface area is double as one of the square bases. What is the length of the body diagonal?
  10. VAT on books
    books_13 The cost of a book in the store is 12.5 euros. How much euros is the VAT of this book? VAT is 10%.
  11. Variance and average
    stat Of the 40 values were calculated average mx = 7.5 and variance sx = 2.25. After the control was found to lack the two items of the values of x41 = 3.8 and x42=7. Correct the above characteristics (mx and sx).
  12. Quadrangular pyramid
    komoly Calculate the surface area and volume of a regular quadrangular pyramid: sides of bases (bottom, top): a1 = 18 cm, a2 = 6cm angle α = 60 ° (Angle α is the angle between the side wall and the plane of the base.) S =? , V =?
  13. Chocolate roll
    chocholate_3 The cube of 5 cm chocolate roll weighs 30 g. How many calories will contain the same chocolate roller of a prism shape with a length of 0.5 m whose cross section is an isosceles trapezoid with bases 25 and 13 cm and legs 10 cm. You know that 100 g of this.
  14. Contract
    clocks_5 8 employees complete the contract for 65 hours. After 17 hours, 3 employees had to leave for another job. How many more hours will the job on contract be fulfilled?
  15. Workers
    work_9 9 workers dig a canal 120 meters long for eight hours. For how long would be dig five workers canal 200 meters long?
  16. Price saleoff
    2digits_1 Shoes standing y euros. At first they were discounted by 12% and then 50% of the new amount. After this double cheapening the cost was exactly 22 euros. Determine the original price of shoes.
  17. Wall diagonal
    cube_6 Calculate the length of wall diagonal of the cube whose surface is 384 cm square.
  18. Unknown number
    5nums_1 Determine the unknown number, which double of its fourth square is equal the fifth its square.
  19. Vacation
    eura_9 Tomas spent 60% of his savings for his weekly vacation. He was 32 € left. How many euros did he have before vacation?
  20. Square s3
    squares_9 Calculate the diagonal of the square, where its area is 0.49 cm square. And also calculate its circumference.

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