Expression of a variable from the formula + time - math problems

Number of problems found: 118

  • Annual growth
    exp_growth2 The population has grown from 25,000 to 33,600 in 10 years. Calculate what was the average annual population growth in%?
  • Volume per time
    inlet How long does fill take for a pump with a volume flow of 200 l per minute fill a cube-shaped tank up to 75% of its height if the length of the cube edge is 4 m?
  • Up and down motion
    ballistic We throw the body from a height h = 5 m above the Earth vertically upwards v0 = 10 m/s. How long before we have to let the second body fall freely from the same height to hit the Earth at the same time?
  • Six painters
    painter Six painters paint an area of 120 m2 in 4 hours. How long does it take for 12 painters to paint 480 m2 with the same performance?
  • Vertical rod
    shadow The vertical one-meter-long rod casts a shadow 150 cm long. Calculate the height of a column whose shadow is 36 m long at the same time.
  • Slow saving in banks
    penize How long will it take to save € 9,000 by depositing € 200 at the beginning of each year at 2% interest?
  • Percentage increase
    exp_growth2 What is the annual percentage increase in the city when the population has tripled in 20 years?
  • Age of family
    age The age of father and son is in the ratio 10: 3. The age of the father and daughter is in a ratio of 5: 2. How old are a father and a son if the daughter is 20?
  • The farmer
    cow The farmer calculated that the supply of fodder for his 20 cows was enough for 60 days. He decided to sell 2 cows and a third of the feed. How long will the feed for the rest of the peasant's herd last?
  • Savings
    500eur The depositor regularly wants to invest the same amount of money in the financial institution at the beginning of the year and wants to save 10,000 euros at the end of the tenth year. What amount should he deposit if the annual interest rate for the annua
  • Hectares of forest
    stromy 12 workers plant 24 ha of forest in 6 days. In how many days will 15 people and 12 people plant the same area?
  • Volume of wood
    wood Every year, at the same time, an increase in the volume of wood in the forest is measured. The increase is regularly p% compared to the previous year. If in 10 years the volume of wood has increased by 10%, what is the number p?
  • Growth of wood
    wood The annual growth of wood in the forest is estimated at 2%. In how many years will make the forest volume double?
  • Pilsen Region
    exp_growth Between 2000 and 2001, 14 per mille of the population decreased in the Pilsen Region. In 2000, the Pilsen Region had 551281 inhabitants. If the declining trend continues the same (i. E. , 14 per mille of inhabitants per year), how many inhabitants will th
  • Two patches
    krizik Peter taped the wound with two rectangular patches (one over the other to form the letter X). The area sealed with both patches at the same time had a content of 40cm2 and a circumference of 30cm. One of the patches was 8cm wide. What was the width of the
  • Where and when
    cars The truck left Kremnica at 11:00 h at a speed of 60km/h. At 12:30 h, the passenger car started at an average speed of 80km/h. How many kilometers from Kremnica will the passenger car reach the truck, and when?
  • Positional energy
    energy What velocity in km/h must a body weighing 60 kg have for its kinetic energy to be the same as its positional energy at the height 50 m?
  • The tractor
    tractor The tractor sows an average of 1.5 ha per hour. In how many hours does it sows a rectangular trapezoid field with the bases of 635m and 554m and a longer arm 207m?
  • Between two bus stops
    bus27 Wanda lives between two bus stops at three-eighths of their distance. He started the house today and found that he would have arrived at the bus stop if he was running to one or the other stop. The average bus speed is 60 km/h. What is the average speed o
  • Drive to NJ
    motion Ed drove to New Jersey at 30mph. He drove back home in 3 hours at 50 mph. How many hours did it take Ed to drive to New Jersey?

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Do you want to convert time units like minutes to seconds? Expression of a variable from the formula - math problems. Time - math problems.