Examples for 7th grade (seventh) - page 55

  1. Cube 2
    krychle_1 How many times will increase if the surface area of the cube if we triple length of its edge?
  2. Joshka
    money-false Joshka had € 15. Mama took him 15%. How many had left?
  3. Unknown number 24
    numbs_6 f we add 20, we get 50% of its triple. What is this unknown number?
  4. Buttons
    knofliky Shirt has 6 buttons, blouse has 4 buttons. All buttons are 176. Shirts and blouses are together 36. How many are the shirts and blouses?
  5. Circle from string
    motuz Martin has a long 628 mm string . He makes circle from it. Calculate the radius of the circle.
  6. Decide
    mo_1 The rectangle is divided into seven fields. On each box is to write just one of the numbers 1, 2 and 3. Mirek argue that it can be done so that the sum of the two numbers written next to each other was always different. Zuzana (Susan) instead argue that.
  7. Charles Bridge
    k_most Charles Bridge was 15 times older than Frantův bridge from 1900 in 1931. How old is the Charles Bridge?
  8. Percentage - fractions
    rubik About what percentage we must increase number 1/6 to get number 1/3?
  9. 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
  10. Perpetrator
    snehulaci The perpetrator is a number that is smaller than the number 80. It is a multiple of five and it is odd. If we added up the tens and ones of this number we get number 8.
  11. Tank
    nadrz_5 To cuboid tank whose bottom has dimensions of 9 m and 15 m were flow 1080 hectoliters of water. This was filled 40% of the tank volume. Calculate the depth of the tank.
  12. Circle - simple
    colorful-circle Calculate the area of a circle in dm2, if its circumference is 31.4 cm.
  13. Trio 2
    decide Decide whether trio of numbers is the side of a right triangle: 26,24,10.
  14. 15 number
    numbers_15 What number is smaller (greater) by 15 than its half?
  15. 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?
  16. 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.
  17. Tank
    24-022W_L How many minutes does it take to fill the tank to 25 cubic meters of water filled 150hl per hour?
  18. 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.
  19. 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.
  20. Cube
    krychle How many times increases the surface area of a cube with edge 23.4 cm if the length of the edge doubled?

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