Algebra - problems - page 25

  1. Painters
    painters The first team of painters would paint bridge in 15 days, the second in 10 days. After 3 days of working together second team goes out and continue only first team. How many days took second team to finish painting the bridge?
  2. Cows
    kravy0 20 cows has food for 60 days. We reduce the dose to two-thirds for 18 cows. How many days will be fed?
  3. Sum-log
    complex_log The sum of two numbers is 32, the sum of their logarithms (base 10) is 2.2. Determine these numbers.
  4. Spartakiada
    spartakiada_1 Practitioners lined up in rectangle with row with four, five or six exercisers, one always missing to full rectangle. How many exercisers were on the field, if they have estimated not been more than 100?
  5. Angles ratio
    triangles_16 The internal angles of a triangle are in ratio 1:4:5 What kind of triangle is it? (solve internal angles and write down and discuss)
  6. Self
    Self-books A math text book is 2 2/9 inches thick. how many of these books will fit on a 120-inch self?
  7. Czech crown salary
    penize_34 The monthly salary of the employee is CZK 10,800. In the course of the year the bulk salary increased by CZK 500. Calculate which month (1 ... 12) was increased if its annual income was 133,600 CZK.
  8. Class 8.A
    trieda_2 Three quarters of class 8.A went skiing. Of those who remained at home one third was ill and the remaining six were on math olympic. How many students have class 8.A?
  9. Interest
    MoneyHouse What is the annual interest rate on your account if we put 32790 and after 176 days received 33939.2?
  10. Disinfecting solution
    desinfect How much distilled water is necessary to pour into 500 ml of 33% hydrogen peroxide solution to obtain 3% disinfecting solution?
  11. Resistors
    resistors Two resistors connected in series give the resulting resistance 216Ω and 48Ω in parallel. Determine the resistance of this resistors.
  12. Ray
    luc-slnka Light ray loses 1/19 of brightness passing through glass plate. What is the brightness of the ray after passing through 7 identical plates?
  13. Soup
    kotlik On Monday we cook 25 pots and 10 boilers of soup. On Tuesday 15 pots and 13 boilers. On Wednesday 20 pots and on Thursday 30 boilers. On Monday and Tuesday was cooked the same amount of soup. How many times more soup cooked on Thursday than on Wednesday?
  14. Electrics - conductor
    wire_2 The wire is 106 meters long at 0 °C and at every temperature increase of 1 °C the length increases by 0.15 mm per 1 m length of wire. Determine a function which represents the overall length of the wire as a function of temperature. What is the length of t
  15. Pedestrian and the cyclist
    cyklista_1 Pedestrian and cyclist went against each from the two cities that are distant 40 km. Pedestrian started 30 minutes before the cyclist and walk an average speed of 5 km/h. What speed went cyclist when met after 120 minutes from the start of the pedestrian?
  16. Glasses
    class Imagine a set of students in your class (number of students: 19), who wears glasses. How much minimum and maximum element may contain this set.
  17. Unknown number
    iks-icon Samuel wrote unknown number. Then he had add 200000 to the number and the result multiply by three. When it calculated he was surprised, because the result would have received anyway, if write digit to the end of original number. Find unknown number.
  18. Square
    squares_4 If we increase one side of square by its one-half then square perimeter increase by 10 cm. What is the side of the square?
  19. Clouds
    cloud From two points A and B on the horizontal plane was observed forehead cloud above the two points under elevation angle 73°20' and 64°40'. Points A , B are separated by 2830 m. How high is the cloud?
  20. Brothers and sisters
    family Lenka has as many brothers as sisters. Her brothers have twice as many sisters as brothers. How many brothers and sisters are in the family?

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