Examples for 7th grade (seventh) - page 17

  1. Machines
    machinery In the workshop are three machines. The first is treated 250 parts for 4.7 hours, the second is treated 300 parts for 1.9 hours and the third is treated 230 parts for 4.6 hours. How long will take to make 3100 parts if worked all three machines at the.
  2. The horses
    kon A couple of horses consume 88 kg of oats for 14 days. How many oats consumed 7 horses at the same consumption for 6 days?
  3. Rhombus
    rhombus_4 Calculate the length of the diagonal AC of the rhombus ABCD, if its perimeter is 84 dm and the other diagonal BD has length 20 dm.
  4. Tank and water
    chemickelaboratorium1 Cylindrical tank were poured with 3.5 liters of water. If tank base diameter is 3 dm, how height is water level in?
  5. Rail turn
    railroad_turn The curve radius on the railway line is 532 m . Length of rail track on it is 818 m. How many degrees is the angle ASB, if A and B are boundary points and S is center of arc curve.
  6. Median
    1taznice_rt In the right triangle are sides a=41 dm b=42 dm. Calculate the length of the medians tc to the hypotenuse.
  7. BMI index
    man_BMI Calculate BMI (body mass index, an index indicating obesity, overweight, normal weight, underweight) man weighing m = 71 kg and height h = 170 cm. Index is calculated according to equation (formula): ? With BMI index is possible to compare people of diff
  8. Tributaries
    pritok The first tributary fill pool with water in 15 hours. The second tributary fill pool in 10 hours. For how many hours the pool is filled with both tributaries?
  9. Series
    posloupnost_an Andrew wrote this series of numbers: 1,3,7,15, .... n. Which number in the series does not belong? ?
  10. Segments
    abs Which of the pairs of numbers on the number line encloses the longest segment: ?
  11. Mushrooms
    huby Fresh mushrooms contain 94% water, dried 14%. How many kg of fresh mushrooms is needed to collect to get 10 kg dried?
  12. Basements
    Spider-and-Fly In the first basement is more flies than the spiders, the second vice versa. Each basement had spiders and flies together 100 feet. Determine how many could be flies and spiders in the first and second basement. PS. We only need, when you write how many.
  13. Elections
    elections The elections attended a total 4818 voters. First day 39 men more than women, the second day 21 women more than men. How many women attended elections?
  14. Rectangular trapezoid
    trapezoids How many inner right angles has a rectangular trapezoid?
  15. Around the flowerbed
    roses Around a rectangular flowerbed with dimensions 5.25 m and 3.5 m are to be planted roses equally spaced so that the roses found in every corner of the flowerbed and consumed them as little as possible. a) At what distance are planted roses? b) How many ros
  16. Circumscription
    circles43 Calculate radius of the Circumscribed circle in the rectangle with sides 20 and 19. It can be rectangle inscribed by circle?
  17. Trapezoid RT
    lichobeznik2 The plot has a shape of a rectangular trapezium ABCD, where ABIICD with a right angle at the vertex B. side AB has a length 36 m. The lengths of the sides AB and BC are in the ratio 12:7. Lengths of the sides AB and CD are a ratio 3:2. Calculate consumptio
  18. Parallelogram
    quadrilateral_parallelogram The perimeter of the parallelogram is 117 cm. The length of one side is 1.9-times longer than the length of the shorter side. What is the length of sides of a parallelogram?
  19. Subway
    metro Subway train went between two stations that gradually accelerated for 26 seconds and reached a speed of 72 km/h. At this rate, went 56 seconds. Then 16 seconds slowed to a stop. What was the distance between the stations?
  20. Car inflation
    car_1 About what percentage price of car increased if price rose from €1880 to €2200?

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