Equation - examples

  1. Poplar
    topole How tall is a poplar by the river, if we know that 1/5 of its total height is a trunk, 1/10th of the height is the root and 35m from the trunk to the top of the poplar?
  2. Average height
    meter_22 The average height of all pupils is 162 cm. The class teacher's height is 178 cm. The average height of all (teacher and all pupils) is 163 cm. Calculate the number of pupils in the class.
  3. The size
    trapezium_6 The size of a Trapezium are 3/4×cm, ×cm 2(×+1)cm and 3(×+2)cm long respectively if it's perimeter is 60cm, calculate the length of each side.
  4. The painter
    painter_12 In order for the painter to get the desired color, he must mix green and yellow in a ratio of 4: 7. If it has 28 l of green color, how many liters of yellow color should he add? How many liters of mixed color does he get?
  5. Construction of road
    truck_14 For the construction of the road dam, it is supposed to transport six trucks a total of 18 days. After three days, two more cars were sent to the construction site. How long will it take to carry the material?
  6. Peter and Paul
    clock-night-schr_16 Peter and Paul together have 26 years. Four years ago, Paul was twice older than Peter. How much is Paul and how much Peter?
  7. Tickets
    cinema2_16 1260 tickets sold. On the first day, 80% was sold on the second day was sold. How many tickets were sold first and how much the next day?
  8. Find the 7
    zlomky_23 Find the number that is smaller than 5 5/12 by as much as 2 2/13 is smaller than 6 1/6
  9. Mushrooms
    hriby_1 Mushrooms lose 90% by weight drying. How many fresh mushrooms are needed for 5 kg of dried mushrooms?
  10. Simplify
    expr_3 Simplify expression - which expression is equivalent to: 3(m + 2) − 4(2m − 9)
  11. Rectangular triangle
    rt_triangle_2 The lengths of the rectangular triangle sides with a longer leg 12 cm form an arithmetic sequence. What is the area of the triangle?
  12. Which
    plusminus_11 Which decimals when subtracted equal 3.89: a - b = 3.89
  13. Grandmother
    car_33 Mom walked out to visit her grandmother in a neighboring village 5km away and moved at a speed of 4km/h. An hour later, father drove down the same road at an average speed of 64km/h. 1) How long will take to catch mom die? 2) What is the approximate dis
  14. Two cyclists 2
    cyclist_45 At the same time, two cyclists left the towns A and B at constant speeds. The first one going from town A to town B, and the second one from town B to town A. At one point of the trip they met. After they met, the first cyclist arrived at town B in 36min,.
  15. Sum of four numbers
    seq_6 The sum of four consecutive natural numbers is 114. Find them.
  16. The rod
    meter_19 The rod has a length of 90cm. Half is painted blue, the third is red and the rest is yellow. How long is the yellow part of the rod?
  17. Sales off
    sale_6 The price has decreased by 20%. How many percents do I have to raise the new price to be the same as before the cut?
  18. Acid evaporation
    roztoky_12 How many kilograms of water do we have to evaporate from 100 kg of 32% acid to make it 80% concentration?
  19. Father and daughter
    time_14 When I was 11 my father was 35 year old. Now, father has three times older then me. How old is she?
  20. Eggs
    egg_2 3400 eggs sliced hens for February and March. We have to calculate how many hens can make 3400 eggs when one hen give 2 eggs a day for 59 days.

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