Expression of a variable from the formula - 6th grade (11y) - math problems

  1. Cube edges
    cube_shield_3 The sum of the lengths of the cube edges is 42 cm. Calculate the surface of the cube.
  2. Unknown number 5
    hyperbola_2 Daniel think an integer. When he change this number at a ratio of 2:5 he got number 2.8. Determine what number think Daniel.
  3. Bus lines
    bus27 Buses connections are started from bus stop on its regular circuit as follows: No. 27 bus every 27 minutes and No.18 every half hour. What time started this two bus lines run if the bus stop met at 10:15 am.?
  4. Euros
    eura_8 Peter spent a quarter of his pocket saving. He has 9 euros now in his wallet . How many euros spent?
  5. Quotient
    math Find quotient before the bracket - the largest divisor 51 a + 34 b + 68 121y-99z-33
  6. Cuboid - Vab
    cuboid_3 Find the surface of the cuboid when its volume is 52.8 cubic centimeters, and the length of its two edges is 2 centimeters and 6 centimeters.
  7. Cuboid surface
    cuboid_4 Determine surface area of cuboid if its volume is 52.8 cm cubic and length of the two edges are 2 cm and 6 cm.
  8. Car consumption
    odometer The car has passed 988 kilometers and consumed 66 liters of petrol. What is the consumption per 100 kilometers?
  9. On the farm
    cows On the farm were housed 70 heads of cattle with food supply for 180 days. After 60 days, 10 head of cattle sold, and for the next 30 days they sold 10 more. How many days is sufficient supply of feed for the remaining cattle?
  10. The tourist
    cyclist_28 The tourist came started from the hostel at an average speed of 5km/h. Half an hour later, the bicyclist started along the same route at a speed of 20km/h. How many minutes will a cyclist catch up and how many kilometers will he go?
  11. 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.
  12. Two thirds
    fractions_10 Find two-thirds of the number equal to two-thirds of 99
  13. Natural gas in kWh
    plynomer Gas consumption for 2017 was 11,301 kWh I paid 532 € How much 1 m3?
  14. Cuboid
    cuboid_12 Cuboid has a surface of 516 cm2. Side a = 6 cm and b = 12 cm. How long is the side c =?
  15. Three pumps
    watertank_2 The water tank is emptied with the first pump in 6 hours, with the second pump in 2 hours. In order to be emptied in 1 hour, all three pumps had to be started at once. How long will take tank be emptied by only the third pump?
  16. Third dimension
    star_1 Calculate the third dimension of the cuboid: a) V = 224 m3, a = 7 m, b = 4 m b) V = 216 dm3, a = 9 dm, c = 4 dm
  17. Divide money 2
    penize_42 Ben and Dan had the same amount of money at the start. When Ben gave 300 to Dan, the ratio of Ben 's money to Dan's money became 2:3. How much money did each have at first?
  18. Bicycle gears
    rear_wheel_sprocket_cassette The toothed wheel on the bicycle pedal has 40 teeth, the wheel on the rear wheel has only 16 teeth. How many times does the rear wheel turn if the pedals rotate 50 times?
  19. Isosceles triangle
    rr_triangle3 The circumference of the isosceles triangle is 32.5 dm. Base length is 153 cm. How long is the leg of this triangle?
  20. Cube edge
    cubes_9 Determine the edges of the cube when the surface is equal to 37.5 cm square.

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