Examples for 7th grade (seventh) - page 31

  1. The carpet
    koberec_1 How many meters of carpet 90 cm wide need to cover floor room which has a rectangular shape with a lengths 4.8 m and 2.4 m if the number of pieces on the carpet is needed to be lowest?
  2. Disjoint
    sets How many elements have union and intersection of two disjoint sets when the first have 1 and secodn 8 elements.
  3. Quiz
    quiz Tested student answered correctly on a 4/ 8 questions. Wrong answers was 16. How many questions answered?
  4. The book
    book The book has 280 pages. Each side is a rectangle with sides 15 cm and 22 cm. a) how many leaves has the book? b) at least how many square meters of paper should be used to production this book?
  5. Lunch
    lunch Jane eats whole lunch for the 30 minutes. Which part of the lunch is eaten in 180 seconds?
  6. Salary increase
    vyplata Ms. Merry salary increased by 15% and that was 83e. What should pay before the increase?
  7. Five tractors
    tractor_1 Five tractors plow field in 4.8 hours. How long plow this field if after 1.5 hours of work two tractors went to a different field?
  8. Wheels
    tractor Small tractor wheel with a diameter of 60 cm must be rotated 8 times to overcome some pathway. How many times must turn the big tractor wheel with a radius 60 cm to overcome the same distance?
  9. Barrel 2
    barell Empty barrel weighs 7 kg. When it filled with water up to 45% height, weighs 60 kg. How heavy is barrel full of water?
  10. Brackets
    brackets Place one pair of brackets in expression 20-16 + 10 - 4 - 2 so that the result will be 0.
  11. Apples and pears
    hrusky2 Mom divided 24 apples and 15 pears to children. Each child received the same number of apples and pears - same number as his siblings. How many apples (j=?) and pears (h=?) received each child?
  12. Tiles
    tiles How many 46 cm square tiles will cover a floor 22.08 m by 8.74 m?
  13. Round table tablecloth
    obrus Round table has area 50.24 dm2. Calculate the diameter of the circular tablecloth, if it is extend beyond the edge of the table by 30 cm.
  14. Every day 7 pages
    books_9 Adelka reads the book every day 7 pages. When she reads one more page a day she will read it three days earlier. How long will Adelka read a book? How much does a book of pages have?
  15. Silo
    silo Outer perimeter of silo is 32 m. Concrete wall is 35 cm thick. What is diameter and area of inside floor of silo?
  16. RT 10
    triangles_rt Area of right triangle is 84 cm2 and one of its cathethus is a=10 cm. Calculate perimeter of the triangle ABC.
  17. Water in aquarium
    akvarko_4 The aquarium cuboid shape with a length of 25 cm and a width of 30 cm is 9 liters of water. Calculate the areas which are wetted with water.
  18. Ratio - rectangle
    rectangles The rectangle has dimensions 6 cm and 9 cm. How many times increases area and its perimeter, when its dimensions increase in the ratio 5:3?
  19. Medians in triangle
    stredne_pricky Median of isosceles triangle has a length 3 cm. Determine the length of its sides if its perimeter is 16 cm.
  20. Motor oil
    olej 30 liters of oil cost 28.80 Euros. How much cost a liter?

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.