Rational numbers + direct relationship - math problems

Number of problems found: 18

  • Server
    p_pro Calculate how many average minutes a year is a webserver is unavailable, the availability is 99.99%.
  • Expansion
    magnification If one side of the rectangle is larger 4-times and second 2-times, what percentage increases the area of rectangle?
  • Beer
    piva After three 10° beers consumed in a short time, there is 5.6 g of alcohol in 6 kg adult human blood. How much is it per mille?
  • Pipes
    water_pipe Water pipe has a cross-section 1087 cm2. An hour has passed 960 m3 of water. How much water flows through the pipe with cross-section 300 cm2 per 9 hours if water flow same speed?
  • Math test
    logo_skola In class 6.A are 26 students and the teacher had managed to give tests to 13 students. 13 testes he gave in 6.5 min. How many pupils still haven't test? How long will it take techer to give tests to 43 students?
  • Youth track
    tunel Youth track from Hronská Dúbrava to Banská Štiavnica which announced cancellation attracted considerable media attention and public opposition, has cost 6.3 euro per capita and revenue 13 cents per capita. Calculate size of subsidies to trip group of 28 s
  • Medicament
    tablets Same type of medicament produces a number of manufacturers in a variety of packages with different content of active substance. Pack 1: includes 60 pills of 600 mg of active substance per pack cost 9 Eur. Pack 2: includes 150 pills of 500 mg of active sub
  • Excavation
    vykop_ryha Mr. Billy calculated that excavation for a water connection dig for 12 days. His friend would take 10 days. Billy worked 3 days alone. Then his friend came to help and started on the other end. On what day since the beginning of excavation they met?
  • Bonus
    moeny Gross wage was 1323 USD including 25% bonus. How many USD were bonuses?
  • Negative percentage
    trabant In 2006, the company had a loss of 11100 Euros. Two years later he was already in profit 50000 Eur. Calculate what percentage of the company increased profits in this two years.
  • Coffee
    coffe In stock are three kinds of branded coffee prices: I. kind......205 Kc/kg II. kind......274 Kc/kg III. kind.....168 Kc/kg Mixing these three species in the ratio 8:5:6 create a mixture. What will be the price of 100 grams of this mixture?
  • Car factory
    VW_logo Carmaker now produce 2 cars a day more than last year, so the production of 70312 cars will save just one full working day. How many working days needed to manufacture 70312 cars last year?
  • Rectangular cuboid
    cuboid_1 The rectangular cuboid has a surface area 5334 cm2, its dimensions are in the ratio 2:4:5. Find the volume of this rectangular cuboid.
  • Freedom
    family_life In the city are 3/9 of women married for 3/6 men. What proportion of the townspeople is free (not married)? Express as a decimal number.
  • ŽSR
    luzianky Calculate fixed annual personnel costs of operating monorail line 118 km long if every 5 km is station, which serve three people - one dispatcher and two switchman in 4-shift operation. Consider the average salary of the employee 885 €.
  • Scale
    pool_1 Swimming pool is long 110 m and 30 m wide. The plan of the city is shown as a rectangle with area 8.25 cm2. What scale is the city plan?
  • Acid
    acid_1 The barrel is 199 litres of 38% acid. How many percent acid occurs when 61 litres revoke and replace it with the same amount of water?
  • Expression
    fractions If it is true that ? is:

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