Examples for 7th grade (seventh) - page 81

  1. Dort
    dort_3 The cube-shaped cube box has the dimensions of 30 cm × 30 cm × 12 cm. How many CZK (Czech crowns) would cost be the biggest cake that would fit into the box when a 10 cm³ cake costs CZK 0.5? The cake has the same shape as the box.
  2. Pamela
    penize_48 Lara Pamela spends her salary of 3000 for food, clothing, recreation and savings, which are in the ratio of 48:20:15:37, respectively. How much does he spend for savings?
  3. Equation 15
    eq222_4 Solve equation with variables on both sides:
  4. Temperature increase
    teplomer_19 If the temperature at 9:am is 50 degrees. What is the temperature at 5:00pm if the temperature increases 4 degrees Fahrenheit each hour?
  5. Hour salary
    usd_8 You work for 4 hours on a Saturday and 8 hours on Sunday. You also receive a $50 bonus. You earn $164. How much did you earn per hour?
  6. The square
    numbers_49 The square root of 25 times the square root of 81 is what number?
  7. Constant motion
    car_36 The car has undergone constant motion 120 km in 1 hour 30 minutes. Determine its average speed. Determine how long car drove in the first 20 minutes and 50 minutes from the start of the move.
  8. Two thirds
    fractions_10 Find two-thirds of the number equal to two-thirds of 99
  9. The aquarium
    akvarko_17 The aquarium has a capacity of 18 liters. What is its height when the square bottom is 8 2/3 cm long?
  10. Game 27
    dice_4 Susan wanted to play the game. In the beginning, the first says a number from 1 to 8. Then the second player adds a number from 1 to 5 and tells the sum. Again, the Susan adds a number from 1-5 and say sum and etc. . . The winner must say the number 27. Wh
  11. Ophelia
    teplomer_9 Ophelia recorded the temperature of a cold store every two hours. 1. At 6am it was -4°C and at 8am it was -1°C. By how much did the temperature rise? 2. The temperature went up by 5°C in the next two hours. .What was the temperature at 10am?
  12. Two gears
    gears-3 The two gears fit together. The larger gear has 32 teeth, the smaller has 20 teeth less. How many times does turn a smaller gear if the bigger gear turns three times?
  13. Negative in equation
    eq1_7 2x + 3 + 7x = – 24, what is the value of x?
  14. Half-sphere roof
    kupola_1 The roof above the castle tower has the shape of a 12.8 m diameter half-sphere. What is the cost of this roof, if the cost of 1 square meter is 12 euros and 40 cents?
  15. Fe metal sheet
    plech_1 For one product, 5/8 of the metal sheet are consumed, to the second 5/6 of remains. What part of the sheet metal is consumed for both products together?
  16. Area to volume
    two_cubes_2 If the surface area of a cube is 486, find its volume.
  17. A cylindrical tank
    tanks_8 A cylindrical tank can hold 44 cubic meters of water. If the radius of the tank is 3.5 meters, how high is the tank?
  18. Building
    wood_3 At the building, we divided 240 boards into two piles in a 5: 3 ratio. How many were fewer boards in the lower pile?
  19. Isosceles triangle
    iso_tr_1 In an isosceles triangle, the length of the arm and the length of the base are in ration 3 to 5. What is the length of the arm?
  20. Employees
    workers_45 Of all 360 employees, there are 11/12 women. How many men work in a company?

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