Examples for 7th grade (seventh) - page 40

  1. Parallelogram ABCD
    paralleogram_1 The area of parallelogram ABCD is 440 cm2. Points M and N are the midpoints of the sides AB and BC. What is the area of a quadrilateral MBND?
  2. Water tank
    nadrz Water tank shape of cuboid has dimensions of the bottom 7.5 meters and 3 meters. How high will reach the water in the tank will flow 10 liters of water per second and the inflow will be open 5/6 hour? (Calculate to one decimal place and the results give in
  3. Unknown number 5
    seven I think unknown number. If we enlarge it five times then subtract 3 and result decreases by 75% we get the number by one greater than the number I think. What number am I thinking?
  4. Waiting room
    fly In the waiting room are people and flies. Together they have 15 heads and 50 legs (fly has 6 legs). How many people and flies are in the waiting room?
  5. Strange x
    pie For what x is true ??
  6. Cube 5
    cubes_10 The content area of one cube wall is 32 square centimeters. Determine the length of its edges, its surface and volume.
  7. Price reduction
    camera Price of camera is 654 USD on sale its price reduced to 411 USD. Calculate the percentage reduction in the price of the camera.
  8. Children
    car_game Less than 20 children is played various games on the yard. They can create a pairs, triso and quartets. How many children were in the yard when Annie came to them?
  9. Book
    math_book John read the book so that it read 30 pages per day. Maxim read 34 pages a day and read it two days earlier than John. How many pages has the book?
  10. Dog
    stvorec_1 Dog is tied to a chain, which is mounted in a corner of the yard. Yard has the shape of a square with a side length of 20 meters. The same long is also dogchain. Are there places in the yard where dog can't reach?
  11. Playing Cards
    cards_1 Kara has 2 times more cards than Dana, Dana has 4× less than Mary. Together they have 728 cards. How many cards has each of them?
  12. Reservoir
    cylinder_Au 6 m long reservoir has a diameter of 2.2 m. What is its surface area in square meters?
  13. Bonbons 2
    bonbons_1 Kilo sweets will cost 260 CZK. The first type has a price per 320 kg, the second type 240 CZK per kg. How many kilos of both kinds of sweets need to prepare a 100 kg mixture ?
  14. Rhombus
    pqrs PQRS is a rhombus. Given that PQ=3 cm & height of rhombus is given 2 cm. Calculate its area.
  15. Mr. Vojta
    penize Mr. Vojta put in the bank 35000 Kč.After a year bank him credited with interest rate of 2% of the deposit amount. How then will Mr. Vojta in the bank?
  16. The port
    port Four ships Berthed in the port. Together sail from a port. The first ship will return to port every two weeks, second ship after 4 weeks, third after 8 weeks and fourth ship after 12 weeks. After how many weeks all the boats gather at the port?
  17. Internal and external angles
    inner_outer_angles_triangle Calculate the remaining internal and external angles of a triangle, if you know the internal angle γ (gamma) = 34 degrees and one external angle is 78 degrees and 40 '. Determine what kind of triangle it is from the size of its angles.
  18. Dusan
    parkets a) Dusan break two same window, which has triangular shape with a length of 0.8 m and corresponding height 9.5 dm. Find how many dm2 of glass he needs to buy for glazing of these windows. b) Since the money to fix Dusan has not, must go to the paint job
  19. Average speed
    earth_2 What is the average speed you have to move the way around the world in 80 days? (Path along the equator, round to km/h).
  20. Turtles Žofka and Julka
    korytnacky Gray wolf kept in his tent turtles Žofka and Julka, which together have 200 years. After 50 years will Julka 2 times older than Žofka. How old are the turtles?

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