Expression of a variable from formula - examples - page 15

  1. 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?
  2. Square s3
    squares_9 Calculate the diagonal of the square, where its area is 0.49 cm square. And also calculate its circumference.
  3. The cylinder base
    valec_4 The cylinder with a base of 8 dm2 has a volume of 120 liters. From a cylinder fully filled with water, 40 liters of water was removed. At what height from the bottom /with precision to dm/ is the water level?
  4. Cows
    cow_3 Agricultural cooperative has increased the number of housed cows by 14% to 285 units. By how many cows increased agricultural cooperative the number of cows?
  5. Cube walls
    krychle_6 Find the volume and surface area of the cube if the area of one wall is 40cm2.
  6. Wine
    vino_1 A bottle of wine costs 21 euros; and wine is 20 times more expensive than a bottle. How much a bottle cost?
  7. Trucks
    bricks Three lorries droved bricks. One drove n bricks at once, second m less bricks than the first and third 300 bricks more the first lorry. The first lorry went 4 times a day the largest went 3 times a day and the smallest 5 times a day. How many bricks br
  8. Tank diameter
    cylinder_5 A cylindrical tank has a volume of 60 hectoliters and is 2.5 meters deep. Calculate the tank diameter.
  9. Holidays - on pool
    pool_4 Children's tickets to the swimming pool stands x € for an adult is € 2 more expensive. There was m children in the swimming pool and adults three times less. How many euros make treasurer for pool entry?
  10. Hypotenuse
    RightTriangleMidpoint_1 Calculate the length of the hypotenuse of a right triangle if the length of one leg is 4 cm and its content area is 16 square centimeters.
  11. Perimeter to area
    circles_1 Calculate the area of a circle with the perimeter 15 meters.
  12. Sphere radius
    koule_krychle_2 The surface of the sphere is 60 cm square. Calculate its radius; result round to tenth of cm.
  13. Table
    stol The circumference of the rectangle table is 420 cm. Length to width ratio is 5:2 . Calculate table dimensions and dimensions reduced in the ratio 3:5
  14. RT perimeter
    rt The leg of the rectangular triangle is 7 cm shorter than the second leg and 8 cm shorter than the hypotenuse. Calculate the triangle circumference.
  15. Trapezoid - central median
    lichobeznik-stredni_pricka The central median divides the trapezoid into two smaller trapezoids. Determines the ratio of their contents.
  16. Raspberries
    maliny_2 Dano had 20 raspberries. John had 90% more raspberries than Dano. Determine how many raspberries have Dano and Juraj together.
  17. Fifth member
    arithmet_seq_1 Determine the fifth member of the arithmetic progression, if the sum of the second and fifth members equal to 73, and difference d = 7.
  18. Rectangle 35
    rectangles_13 Find the area of a rectangle when the diagonal is equal to 30 cms and the width is double the length.
  19. Regular n-gon
    10gon_polygon In a regular n-angle polygon the internal angle is 144 degrees. Find the number n indicating the number of sides of this polygon.
  20. Arithmetic progression
    postupnost1_4 In some AP applies: 5a2 + 7a5 = 90 s3 = 12 Find the first member a =? and difference d = ?

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