Examples for 7th grade (seventh) - page 56

  1. Circle - simple
    colorful-circle Calculate the area of a circle in dm2, if its circumference is 31.4 cm.
  2. Unknown number
    nums Identify unknown number which 1/5 is 40 greater than one tenth of that number.
  3. Common cylinder
    valec_2 I've quite common example of a rotary cylinder. Known: S1 = 1 m2, r = 0.1 m Calculate : v =? V =? You can verify the results?
  4. Trio 2
    decide Decide whether trio of numbers is the side of a right triangle: 26,24,10.
  5. Wood lumber
    hranol_7 Wooden lumber is 4 m long and has a cross section square with side 15 cm. Calculate: a) the volume of lumber b) the weight of the lumber if 1 m3 weighs 790 kg
  6. 15 number
    numbers_15 What number is smaller (greater) by 15 than its half?
  7. Tank
    24-022W_L How many minutes does it take to fill the tank to 25 cubic meters of water filled 150hl per hour?
  8. 2d shape
    semicircles_rect Calculate the content of a shape in which an arbitrary point is not more than 3 cm from the segment AB. The length of the segment AB is 5 cm.
  9. Sales off
    save_now Calculate what was the original price of the good, if the price after discount 25% and the subsequent rise of 20% is 400 USD.
  10. Cube
    krychle How many times increases the surface area of a cube with edge 23.4 cm if the length of the edge doubled?
  11. Plot
    parcela_1 The plot on which Mr. Kalous is to build a house has the shape of a rectangle. On a 1: 500 scale, its dimensions are 7cm and 5.5cm. Find out the dimensions of the plot. Calculate the parcel size.
  12. Troops
    army If the general sorts troops into the crowd by nine left 6. How many soldiers has regiment if we know that they are less than 300?
  13. Log
    5962705_ad Worker cut his thick log to 6 pieces for 30 min. How long he cut log to 12 pieces?
  14. Addends
    two Number 118 divide into two addends, so first addend is 69 greater than 75% of the second addend.
  15. Potatoes
    zemiaky_3 Daniela and Michael would jointly dug potatoes for 7.5 hours. But if Daniela was working alone she would take 2.5 hours more as if he were working with Michael. Determine how much for the work done by Michael himself and how much Daniela herself.
  16. Car model
    cars_2 Car model is 52 mm long and the real car is 4524 mm long. What was the scale of model car?
  17. Megapascals
    engine What is the area of crosssection of the piston, if the force of 300 kN produces a pressure of 5 MPa?
  18. 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?
  19. Z7-I-4 stars 4949
    hviezdicky_mo Write instead of stars digits so the next write of product of the two numbers to be valid: ∗ ∗ ∗ · ∗ ∗ ∗ ∗ ∗ ∗ ∗ 4 9 4 9 ∗ ∗ ∗ ∗ ∗ ∗ 4 ∗ ∗
  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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