Latest problems - page 5

  1. Three friends
    penize_49 Cuba, Matthew and their friend Adam found a brigade during their weekend weekends because they wanted to make a joint trip to the Alps that they planned for the spring break. Cuba enjoyed the skiing trip very much, so he was not lazy to get up and went t
  2. Vinegar mixing
    vinegar_2 We mix 70g water and 50g 8% vinegar. How many percents of the solution of vinegar we produce?
  3. Area to volume
    two_cubes_2 If the surface area of a cube is 486, find its volume.
  4. Two trains
    rjet Through the bridge, long l = 240m, the train passes through the constant speed at time t1 = 21s. A train running along the traffic lights at the edge of the bridge passes the same speed at t2 = 9s. a) What speed v did the train go? b) How long did it tak
  5. 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.
  6. Mushrooms
    hriby Fresh mushrooms contain 88% water, dried 14% water. How many kilograms of fresh mushrooms should be collected to get 3 kg of dried?
  7. Calculate 2
    t_sss Calculate the largest angle of the triangle whose side are 5.2cm, 3.6cm, and 2.1cm
  8. Far country
    dukat_2 In a country far away, the value of 3 pesos is 12 centavos more than the value of 1 peso. How many centavos is 1 peso worth?
  9. Workers
    Clock0400_9 Three factory operators produced 480 units in 50 minutes. How many hours worked? I'm trying to prove or disapprove the idea that the company tell me that it's 2.5 hours. So what is right? Thank you, Petra
  10. Waste
    doska_kruh How many percents are waste from a circular plate with a radius of 1 m from which we cut a square with the highest area?
  11. Substitution method
    500px-Sine_cosine_plot.svg Solve goniometric equation: sin4 θ - 1/cos2 θ=cos2 θ - 2
  12. The florist
    ruze_6 The florist had 200 roses in the morning. During the day, more than half sold it. From the remaining roses, it will tie the bouquet. If a bouquet of 3, 4, 5 or 6 roses are bound, one always remains. How many roses from the morning shipment sold?
  13. Reduce to lowest terms
    fractions_16 Reduce to lowest terms : 32/124
  14. The lowest
    teplomer_20 The lowest temperature on Thursday was 20°C. The lowest temperature on Saturday was 12°C. What was the difference between the lowest temperatures?
  15. Flooring a room
    tiles_10 Find the cost of flooring a room 6.5 m by 5 m with square tiles of sides 25 cm at the rate of rupees 9.40 per tile.
  16. The average
    average The average of one set of 4 numbers is 35. The average of another set of number is 20. The average of the numbers in the two sets is 30. How many numbers are there in the other set?
  17. Families 2
    family_24 There are 729 families having 6 children each. The probability of a girl is 1/3 and the probability of a boy is 2/3. Find the the number of families having 2 girls and 4 boys.
  18. Coal mine
    coal_5 The monthly plan of 17,000 tons of coal exceeded the mine by 1/25. How many tonnes of coal have been harvested from the mine above plan?
  19. Discount sale
    penize_49 After the discount, the computer costs 9600, - CZK. How much did it cost when the price was reduced: a) by half b) by a third c) by one fifth and then by 160 CZK
  20. Fractions 4
    fractions_14 How many 2/3s are in 6?

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