Examples for 7th grade (seventh)

  1. Prism
    hranol_3bokovy_1 Find the volume and surface area of prism with base of an equilateral triangle with side 7 dm long and the body height of 1.5 m.
  2. Wood cuboid
    dub What is the weight of the wood cuboid 15 cm, 20 cm, 3 m if 1 m3 wood weighs 800 kg?
  3. Freezer
    mraznicka The freezer has the shape of a cuboid with internal dimensions of 12 cm, 10 cm, 30 cm. A layer of ice of 23 mm thick was formed on the inner walls (and on the opening) of the freezer. How many liters of water will drain if we dispose the freezer?
  4. Prism - eq triangle
    prism-3sides_1 Calculate the volume and surface of the prism with the base of an equilateral triangle with side a = 4cm and the body height is 6cm.
  5. Cents no more
    cent Janko bought pencils for 35 cents each. Neither he nor the salesperson had small coins just a whole € 1 coin. At least how many pencils had to buy to pay for the whole euros?
  6. The cube
    kostka The surface of the cube is 150 square centimeters. Calculate: a- the content of its walls b - the length of its edges
  7. The wall
    wall_mur We have to build a cuboid wall with dimensions base 30 cm and 45 cm and height 3.25 meters. Calculate how many we need bricks if we spend 400 pieces of bricks to 1 m3 of wall?
  8. Tractors
    tractor_2 Six tractors plowing the field for 8 days. After two days, two tractors broke down. How many days were prolonged work in the field?
  9. Land area
    world_map_000 A land area of Asia and Africa are in a 3: 2 ratio, the European and African are is 1:3. What are the proportions of Asia, Africa, and Europe?
  10. Mother and daughter
    kresba_1 The ratio of years mother and daughter is 5:2. After 7 years the ratio is 2: 1. How many years ago daughter was born?
  11. Wallet
    berries From the money that was in my Maria wallet she spent a fifth on the first purchase. From remain money she could buy 2 kg of strawberries. But she bought only 1.5 kg for 60 Kc. How much money was Marie originally in her wallet?
  12. Water inlets
    pipe Inlet valve with a flow rate of 12 liters per second is filled tank for 72 minutes. How long take to fill full tank if we open one more such valve half an hour after?
  13. Millionaire
    money_7 Mr. Smith have gone withdraw from bank saving interest € 1,500. How big was his initial deposit if the annual interest rate is 1.5%?
  14. Math heart
    srdce_1 Stylized heart shape created from a square with side 5 cm and two semicircles over his sides. Calculate the content area and its circumference.
  15. Unknown number
    nums Identify unknown number which 1/5 is 40 greater than one tenth of that number.
  16. Circle r,D
    bavlnka Calculate the diameter and radius of the circle if it has length 52.45 cm.
  17. Assistant
    psaci-stroj Assistant rewrote 15% of the entire manuscript in 12 hours. How many hours must still write to rewrite the rest of the manuscript?
  18. Profitability
    zisk The purchase price of goods is 13000, the sales price is the 20000. What is the profitability as a percentage?
  19. Division of money
    euro Calculate how many euros have Matthew, Miriam, Lucy, Michael, Janka when together have 2,700 euros and the amounts are at a ratio of 1:5:6:7:8.
  20. After 16 years
    diana After 16 years will Dana be five times older as she was four years ago. After how many years will Dana celebrate her 16th birthday?

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