Grade - examples - page 197

  1. Two trains
    vlak_8 From station A, the freight train traveled at a speed of 40 km/h in 9h. When he drove 15km, the fast train started from station A in the same direction at a speed of 70km/h. When will it the freight train catch up?
  2. Rectangles
    rectangles2_3 How many different rectangles with sides integers (in mm) have a circumference exactly 1000 cm?
  3. Find two
    eq222_7 Find two consecutive natural numbers whose product is 1 larger than their sum. Searched numbers expressed by a fraction whose numerator is the difference between these numbers and the denominator is their sum.
  4. Beds
    stan_3 At the summer camp, there are 41 chalets. Some rooms are 3-beds, some 4-beds. How many campers from 140 are living in 3-bed?
  5. Square into three rectangles
    stvorcove-cisla_1 Divide the square with a side length of 12 cm into three rectangles with have the same circumference so that these circumferences are as small as possible.
  6. Railroad
    trains_7 The railroad runs parallel to the railway. The train travels at 36 km/h on track. In the opposite direction, the motorcycle rides at 90 km/h. The train passes in 3 seconds. How long is a train?
  7. Marriage sttus
    family_26 In our city, there are 3/5 of the women married to 2/3 of the men. Find what part of the population is free.
  8. The swimmer
    river_3 The swimmer swims at a constant speed of 0.85 m/s relative to water flow. The current speed in the river is 0.40 m/s, the river width is 90 m. a) What is the resulting speed of the swimmer with respect to the tree on the riverbank when the swimmer motion
  9. Two numbers
    scientific_2 Find the four times smaller number for numbers 12 and 36 and then add them.
  10. Rectangle - area, perimeter
    rectnagles_2 The area of a rectangular field is equal to 300 square meters. Its perimeter is equal to 70 meters. Find the length and width of this rectangle.
  11. SSA and geometry
    ssu_veta The distance between the points P and Q was 356 m measured in the terrain. The PQ line can be seen from the viewer at a viewing angle of 107° 22 '. The observer's distance from P is 271 m. Determine the viewing angle of P and observer.
  12. Mixing water
    teplomer_17 The 30-liter container should we fill with water at 60 degrees Celsius. How many liters of water 80 degrees C hot and how many liters of water 20 degrees Celsius warm we have to mix?
  13. Barrel with water
    sudy_5 The water barrel has a weight of 52 kg. When we pour a quarter of the water, the weight of the barrel is reduced to 40 kg. Determine the weight of the empty barrel.
  14. Bridge cards
    cards2 How many bridge hands are possible containing 4 spades,6 diamonds, 1 club, and 2 hearts?
  15. Simple equations
    enc2 Solve system of equations: 5x+3y=5 5x+7y=25
  16. Summer tires
    workers_44 Three tire servants have to change the summer tires on 6 cars in 2 hours. Mark's replacement would take 4.5 hours, Jirka would do it in 3 hours and 10 minutes, and Honza in 4 hours. Will they be able to replace all tires at the desired time?
  17. Symbols
    my If 2*3 = 60 ; 3*4 = 120 and 4*5 = 200, what is 2*5?
  18. Clothes
    dvojice_2 Danka and Janka collect clothes. Danka had 9 more than Janka, so she gave her 7. Which now has more cloth and how many?
  19. There
    jablone_12 There are 32 trees of three species in the orchard. 25% cherries, three eighty pears, others plums. How many plums are in the orchard?
  20. Integer
    abs1 Find the integer whose distance on the numerical axis from number 1 is two times smaller as the distance from number 6.

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