Exponential equation - math word problems

Number of problems found: 47

  • Decibel
    tv_1 By what percentage does the sound intensity increase if the sound intensity level increases by 1 dB?
  • 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?
  • Exponential decay
    exponentialFexsDecay A tank contains 55 liters of water. Water is flowing out at the rate of 7% per minute. How long does it take to drain the tank?
  • What is
    exp_growth2 What is the annual percentage increase in the city when the population has tripled in 20 years?
  • Pilsen circus
    cirkus The arrival of the circus in Pilsen was seen in the morning at 08:00 by a citizen of the city. He passed this information on 08:15 to three other residents of the city. Each of these three people then informed the other three residents at 08:30, and again
  • Savings
    bankovka 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
  • 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?
  • One third power
    cube-root Which equation justifies why ten to the one-third power equals the cube root of ten?
  • Before yesterday
    percent He merchant adds a sale sign in his shop window to the showed pair of shoes in the morning: "Today by p% cheaper than yesterday. " After a while, however, he decided that the sign saying: "Today 62.5% cheaper than the day before yesterday". Determine the
  • Water lilies
    lekno_2 Water lilies are growing on the pond and their number is doubled every day. The whole layer is covered in 12 days. How many days will it cover 8 layers?
  • Investment 2
    exp_growth2 Jack invested $5000 in a 5-month term deposit at 4.7% p. A. . At the end of the 5-months, jack reinvested the maturity value from the first deposit into an 11-month term deposit at 7.3% p. A. What is the maturity value at the end of the second term deposi
  • Six speeds
    gears-3 A drilling machine is to have 6 speed ranging from 50 to 750 revolution per minute. If the speed forms a geometric progression, determine their values.
  • Exponential equation
    exp_8 Determine the value of having y in the expression (3^y): (4^-1)=36. Unknown y is a natural number greater than zero.
  • Exponential equation
    exp_8 Solve for x: (4^x):0,5=2/64.
  • Photocopier
    picture A photocopier enlarges a picture in the ratio 7:4. How many times will a picture of size 6cm by 4cm be enlarged to fit on a 30cm by 20 cm page?
  • Radioactive material
    radium A radioactive material loses 10% of its mass each year. What proportion will be left there after n=6 years?
  • An investment
    exp_growth2 How long will it take for an investment to double at a simple interest rate of 5.10% p. A. ? Express the answer in years and months, rounded up to the next month.
  • Exponential equation
    exp Find x, if 625 ^ x = 5 The equation is exponential because the unknown is in the exponential power of 625
  • Microorganisms
    microorganisms The first generation of micro-organisms has a population of 13500 members. Each next generation is 11/10 times the previous one. Find out how many generations will reach at least three times members of the first generation.
  • Powers 3
    exp_4 2 to the power of n divided by 4 to the power of -3 equal 4. What is the vaule of n?

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