Examples for 7th grade (seventh) - page 45

  1. The classroom
    school In the seventh class the number of boys and girls are at a ratio of 4:5. Boys are 16. How many total students are in the classroom?
  2. Wheel
    bicycle_1 Diameter of motocycle wheel is 52 cm. How many times rotates wheel on roand long 2 km?
  3. 3 years
    ekonomicky-rast The company has increased the number of employees. In year 2005 compared to 2004 13% more, in 2006 18% more against the previous year, in year 2007 20% more compared to 2006. How many % increase in the number of employees in 3 years?
  4. Tripled square
    squares4_1 If you tripled the length of the sides of the square ABCD you increases its content by 200 cm2. How long is the side of the square ABCD?
  5. Runners circle
    runners Pepa circles the track in 36 seconds. Kamil in 42 seconds. They started together. How many seconds will meet again at the start?
  6. Ethnicity
    indian Share of ethnicity XY is 26%, which is 1/9 more than in the prewar period. What was the share of that ethnicity in the pre-war period?
  7. Photo egative
    negativ Negative dimensions are 36mm and 28mm. What will be the photo size in the 21:4 ratio?
  8. Percent chaining
    meter_1 Calculate 20% from 70% from 80 km
  9. Three buses
    3buses Three public transport buses depart together from the bus station in the morning. The first bus was returning to the station after 18 minutes, the second after 12 minutes and a third after 24 minutes. How long will again together on the station? Result exp
  10. Prism
    hranol_3bokovy_1 Find the volume and surface area of prism with base of an equilateral triangle with side 7 dm long and the body height of 1.5 m.
  11. Farm2
    pecene_kure The farm bred turkeys, geese, hens and chickens. Everything is 400. Turkeys and geese a hen are 150. No hen has more than one chicken, but some hens has no chick. Half of them is also a quarter of the chickens. When the turkey subtracting 15, we get 75. Ho
  12. Trams 2
    trams_1 Square passes two lines of tram. One running every nine minutes, a second interval of 15 minutes. Exactly at 12 o'clock arrived two tram lines in the square. How soon should a similar situation arise again?
  13. Two rooms
    clean_1 Woman cleans the room in 30 minutes a man in 90 minutes. How long will take they clean two rooms?
  14. Tiles
    wall-tiles-img-5 How many square tiles with the content 121 cm2 has to be ordered for the paving of the square room with a side length of 2.75 meters?
  15. Algebrogram
    plus_2 Solve algebrogram: mama+anna=vari How many solutions are?
  16. Coal
    coal If the daily consumption of 1.6 tons of coal, it is sufficient to supply the boiler for 42 days. How long is sufficient to supply when will burn only 1.2 tons of coal a day ?
  17. Double percent
    percents What is 80% of 60% of 2800?
  18. Mother and daughter
    kresba_1 The ratio of years mother and daughter is 5:2. After 7 years the ratio is 2: 1. How many years ago daughter was born?
  19. 7 roses
    roses_1 Peter buys 7 roses. When he pay for it left him 4 euro. If he bought 5 roses left him 40 euros. How many euros had Peter before buying?
  20. Sea water
    salt_5 One tonne of sea water contains 25 kg of salt. How many tonnes of sea water need to be evaporated to obtain 1 tonne of salt?

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