Examples for 7th grade (seventh) - page 8

  1. Prism
    cuboid_2 Three cubes are glued into prism, sum of the lengths of all its edges is 115 cm. What is the length of one edge of the original cube?
  2. Rhombus 2
    koso Calculate the area of rhombus which has a height v=48 mm and shorter diagonal u = 60 mm long.
  3. Plums
    svestka In the bowl are plums. How many would be there if we can divide it equally among 10, 12 and 14 children?
  4. Bicycle wheel
    bicycle Bicycle wheel has a diameter of 70 cm. Approximately how many times the wheel rotates at 4.7 km long trip?
  5. Cube
    kocka_rubik The cube weighs 24 kg. How weight is cube of the same material, if its dimensions are 2-times smaller?
  6. Number ratio
    ratio2 Calculate two positive numbers that its ratio is 6:6 and difference was 0.
  7. Circle
    circle How big is area of circle if its circumference is 80.6 cm?
  8. Ratio
    ratio_1 6 numbers are in the ratio 1:5:1:5:5:5. Their sum is 242. What are the numbers?
  9. Speed of Slovakian trains
    zssk_train Rudolf decided to take the train from the station 'Trnava' to 'Zemianske Kostoľany'. In the train timetables found train R 725 Remata : km0Bratislava hl.st.12:574Bratislava-Vinohrady13:0113:0219Pezinok13:1213:1346Trnava13:3013:3263Leopoldov13:4514:0168H
  10. Metallurgical enterprise
    iron_industry Metallurgical company daily produces 318 tons of cast iron. How many tons of coke it burns to melt cast iron when 10 tons of cast consumes 6 tons of coke?
  11. Right isosceles
    right_isosceles_triangle Calculate area of the isosceles right triangle which perimeter is 49 cm.
  12. Plumber
    klempir Plumber had to cut the metal strip with dimensions 380 cm and 60 cm to the largest squares so that no waste. Calculate the length of the sides of a square. How many squares cut it?
  13. Chocolate
    cokolada_1 How many times should be broken chocolate consisting of 10 × 12 pieces to get the 120 parts?
  14. Air
    air_room_people Room is 40.1 m long, 25.2 dm wide and 369 cm high. How many people can simultaneously be in this room if for hygiene reasons is calculated 5100 dm3 of air per person?
  15. Parquet floor
    Parkett Three workers laid parquet floor for 2.9 hour. The first one would do this work alone 9 hours, the second in 7 hours. For how many hours would fulfill this work the third worker, if he worked alone?
  16. Pool
    bazen Mr. Peter build a pool shape of a four-sided prism with rhombus base in the garden. Base edge length is 8 m, distance of the opposite walls of the pool is 7 m. Estimated depth is 144 cm. How many hectoliters of water consume Mr. Peter to fill the pool?
  17. Cu wire
    medeny-drat Copper wire has a length l = 980 m and diameter d = 8 mm. Calculate the weight if density of copper is ρ = 8500 kg/m3. Result round to one decimal place.
  18. Radius
    green_circle Determine the radius of the circle, if its perimeter and area is the same number.
  19. Discount
    sales_discount Product has been discounted twice by 19%. What is the total discount given?
  20. Seedcake
    pletenky Seedcake costs 44 cents. How many minimum seedcakes we must buy that we can pay in cash only whole euros?

Do you have an interesting mathematical example that you can't solve it? Enter it, and we can try to solve it.



To this e-mail address, we will reply solution; solved examples are also published here. Please enter e-mail correctly and check whether you don't have a full mailbox.