Examples for 7th grade (seventh)

  1. Square glass
    sklo What is the area of the square window glass with the side 4 dm? Do you know how many cm2 is it?
  2. Rhumbline
    kosodélník Find circumference and area of the rhumbline ABCD if the short side AD of which has a length of 5 cm, and the heel of the height from D leading to the AB side divides the AB side into two sections of 3 cm and 4 cm.
  3. Canister
    kanister Gasoline is stored in a cuboid canister having dimensions 44.5 cm, 30 cm, 16 cm. What is the total weight of a full canister when one cubic meter of gasoline weighs 710 kg and the weight of empty canister is 1.5 kg?
  4. Equation with x
    eq2_3 Solve the following equation: 2x- (8x + 1) - (x + 2) / 5 = 9
  5. Charles Bridge
    k_most Charles Bridge was 15 times older than Frantův bridge from 1900 in 1931. How old is the Charles Bridge?
  6. Proportion
    proportion write the following proportion 8 is to 64 as to 2 is to x
  7. Broken tree
    stromy_4 The tree is broken at 4 meters above the ground and the top of the tree touches the ground at a distance of 5 from the trunk. Calculate the original height of the tree.
  8. Hall
    zamkova_dlazba_3 Rectangular hall will have pave by square tiles with a side length 15 cm. The hall has length 18 meters and width 3 m. How many tiles need to buy if 2 percent of the amount is disrupted during the work?
  9. Class
    children_2 In a class are 32 pupils. Of these are 8 boys. What percentage of girls are in the class?
  10. Sunflower Field
    sunflower_1 The trapezoidal sunflower field is located between two parallel paths which are spaced 230 meters apart. The lengths of the parallel sides of the field are 255 m and 274 m. How many tons of sunflower will come from this field if the hectare yield is 2.25
  11. Rectangular triangle PQR
    solving-right-triangles In the rectangular triangle PQR, the PQ leg is divided by the X point into two segments of which longer is 25cm long. The second leg PR has a length 16 cm. The length of the RX is 20 cm. Calculate the length p of side RQ. The result is round to 2 decima
  12. Grandmother
    cukriky_3 Grandmother wants to give the candies to grandchildren that when she gives 5 candy everyone 3 missing and when she gives 4 candies 3 is surplus. How many grandchildren has grandmother and how many candies has?
  13. Elevator
    vytah The panel house has ten over-ground floors and four underground. The lift goes from the ground floor to 2nd floors, then goes down to 3rd underground floors, then 9 floors up and finally 4 floors down. To what story elevator come? How many floors did it c
  14. Cost reduction
    penize_3 Windbreaker cost after discounted SKK 1275, which were 3/4 of original price. How many SKK originally cost windbreaker? How many SKK was cost reduction?
  15. Cuboid - edges
    kvader_abc The cuboid has dimensions in ratio 4: 3: 5, the shortest edge is 12 cm long. Find: (A) the lengths of the remaining edges, (B) the surface of the cuboid, (C) the volume of the cuboid
  16. Five pumps
    diesel2 Three same pumps fill the tank with 50400 liters of diesel in 7 hours. How many liters of diesel will it take in 4 hours if we add two more of the same pumps and pump them the same way? How much more (or less) will they get if we add 2 of the same pumps
  17. Rectangle from string
    obdelnik String 12m. Make rectangle when one side is two times longer than its width.
  18. Sputnik
    sputnik The first Earth satellite was flying at speed 8000 m/s. At that rate he circled the earth in 82 minutes. Jet flies at an average speed 800 km/h. How long would it take circle the earth round?
  19. Cylindrical tank
    valec_7 Cylindrical tank holds 600hl water and is deep 2.5 m. Calculate the diameter of the cylinder.
  20. Tree shadow 3
    stromy_1 What is the diameter of a tree around which is 3m 9dm 7cm long rope wrapped? How big is its cross-sectional area?

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