Examples for 7th grade (seventh) - page 30

  1. Quadrilateral
    diamond_2 In the square ABCD point P is in the middle of the DC side and point Q in the middle pages AD. If the area of quadrilateral BQPC is 49 cm2, what is the area of ABCD?
  2. Equation with fractions
    go Solve equation: ? It is equation with fractions.
  3. Car - road
    car Car started at 11:40 at speed 54 km/h from A and to B arrived at 12:20. Determine the distance A and B.
  4. Rabbits
    zajace_1 Michael breeding rabbits. His 7 rabbits will eat 98 feed rations for 7 days. How many equal portions of feed should be eat 5 rabbits in 6 days?
  5. Office rent
    futbal-stadion For rent 1m2 of office space is paid €165 per year. How much is the annual rent for an office as big as a football field with dimensions 71.5 m and 102.5 m?
  6. Midpoint of segment
    midpoint-segment Point A has coordinates [-16; 23] and the midpoint of the segment AB is the point [2; 12]. What are the coordinates of point B?
  7. Average
    gaussian Average of 7 numbers is 65. What is its sum?
  8. Czech crowns
    KC.JPG Small Petra save money. Grandfather give her 10 crowns. Petra asked his older sister let her calculate how much he has saved up. Sister told her that he has less than 30 crowns. If the sum is divided by three left one crown. If the sum is divided by the f
  9. Rectangle and circle
    rectangle_circle_desc The rectangle ABCD has side lengths a = 40 mm and b = 30 mm and is circumscribed by a circle k. Calculate approximately how many cm is circle long.
  10. Trees
    trees_1 Loggers wanted to seed more than 700 and less than 800 trees. If they seed in rows of 37, left them 8 trees. If they seed in rows of 43, left the 11 trees. How many trees must seed ?
  11. Machines 2
    machine_1 2 machines for 50 hours produces 2,000 products. How many machines need to buy to make in 30 hours 15,000 products?
  12. Oil tank and pipes
    oil_tank The underground oil tank can be filled by two oil pipelines. The first is filled in 72 hours and the second in 48 hours. How many hours from the moment when first pipeline began to fill the oil is it necessary to start filling it with the second to fill in
  13. Clocks
    clocks How long track travel the second hand in 46 hours, the end of which is 4 cm long.
  14. Octagon from rectangle
    8gon From tablecloth rectangular shape with dimensions of 4 dm and 8 dm we cuts down the corners in the shape of isosceles triangles. It thus formed an octagon with area 26 dm2. How many dm2 we cuts down?
  15. Tons of coal
    coal_2 Coal hopper has a capacity of 285 liters. How many tons is it? The bulk density of coal is 916 kg/m3.
  16. Bakery
    bread_1 How heavy must prepare bread at a bakery if lose during baking 16% of water and after baking must have 2 kg? (Calculate to the nearest gram)
  17. Tractors
    tractor 6 tractors started plowing the field that them together take 12 days. Agronomist hesitates to A) after 2 days to withdraw 2 tractors, or B) after 3 days to withdraw 3 tractors. Help him which of these two cases will be plowing done sooner.
  18. Deposit 3
    interest_money After a year had Martin on bank account € 2028. What was the interest rate when the initial deposit was € 1879?
  19. Water in body
    Water-in-human-body Water in the human organism of all the compounds represented, constitutes about 3/5 of the total weight. How many kilograms of water is in your body when you weigh 67 kg?
  20. Circular flowerbed
    sustredene_kruznice Circular flowerbed with diameter 8 m we split by concentric circle to circle and annulus with the same area. Determine the radius of the circle.

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