Algebra - problems - page 32

  1. Machines 2
    machine_1 2 machines for 50 hours produces 2,000 products. How many machines need to buy to make in 30 hours 15,000 products?
  2. Oil tank and pipes
    oil_tank The underground oil tank can be filled by two oil pipelines. The first is filled in 72 hours and the second in 48 hours. How many hours from the moment when first pipeline began to fill the oil is it necessary to start filling it with the second to fill in
  3. CZK coins
    CZK-coins Thaddeus and Jolana together have 15 CZK. Jolana has half of Thaddeus money. Nevertheless Jolana has 3 coins and Thaddeus 2 coins. Which coin has Thaddeus and Jolana (Help: CZK coins has values 1,2,5,10,20,50 CZK)?
  4. Bakery
    bread_1 How heavy must prepare bread at a bakery if lose during baking 16% of water and after baking must have 2 kg? (Calculate to the nearest gram)
  5. Sequence 3
    75 Write the first 5 members of an arithmetic sequence: a4=-35, a11=-105.
  6. Circular flowerbed
    sustredene_kruznice Circular flowerbed with diameter 8 m we split by concentric circle to circle and annulus with the same area. Determine the radius of the circle.
  7. Bottle
    bottle Bottle with wine costs 58 USD. Wine is 27 USD more expensive than the empty bottle. How much is the bottle itself?
  8. Friends
    friends2 Some friends had to collect the sum 72 EUR equally. If the three refused their part, others would have to give each 4 euros more. How many are friends?
  9. Three friends
    Veverka Three friends squirrels together went to collect hazelnuts. Zrzecka he found more than twice Pizizubka and Ouska even three times more than Pizizubka. On the way home they talked while eating and was cracking her nuts. Pizizubka eaten half of all nuts whi
  10. Quiz
    quiz Tested student answered correctly on a 4/ 8 questions. Wrong answers was 16. How many questions answered?
  11. The carpet
    koberec_1 How many meters of carpet 90 cm wide need to cover floor room which has a rectangular shape with a lengths 4.8 m and 2.4 m if the number of pieces on the carpet is needed to be lowest?
  12. Three digits number
    3digit From the numbers 1, 2, 3, 4, 5 create three-digit numbers that digits not repeat and number is divisible by 2. How many numbers are there?
  13. Handmade baskets
    kosiky Worker knits the baskets which then sells in the market. He maked seven baskets on Monday and one more each day than he did in the previous day. How many times more baskets did he make till the following Monday evening compared to the first day when he di
  14. RT and circles
    r_triangle Solve right triangle if the radius of inscribed circle is r=9 and radius of circumscribed circle is R=23.
  15. Car value
    car_old The car loses value 15% every year. Determine a time (in years) when the price will be halved.
  16. Sum of series
    question Determine the 6-th member and the sum of a geometric series: 5-4/1+16/5-64/25+256/125-1024/625+....
  17. Disjoint
    sets How many elements have union and intersection of two disjoint sets when the first have 1 and secodn 8 elements.
  18. Chicken and rabbits (classic)
    zajace Grandmother breeding chickens and rabbits. It found that the yard has 35 heads and 108 legs. How many chickens and rabbits breeding in the yard?
  19. Miraculous tree
    tree Miraculous tree grows so fast that the first day increases its height by half the total height of the second day by the third, the third day by a quarter, etc. How many times will increase its height after 6 days?
  20. Height of the arc - formula
    sircular_segment Calculate the height of the arc if the length of the arc is 77 and chord length 40. Does exist a formula to solve this?

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