Logarithm - math problems

Number of problems found: 51

  • Poisson distribution - daisies
    Poisson_distribution The meadow behind FLD was divided into 100 equally large parts. Subsequently, it was found that there were no daisies in ten of these parts. Estimate the total number of daisies in the meadow. Assume that daisies are randomly distributed in the meadow.
  • Two geometric progressions
    exp_growth Insert several numbers between numbers 6 and 384 so that they form with the given GP numbers and that the following applies: a) the sum of all numbers is 510 And for another GP to apply: b) the sum of entered numbers is -132 (These are two different geome
  • If you 4
    exp_growth If you deposit $2500 in an account paying 11% annual interest compounded quarterly, how long until there is the $4500 in the account?
  • If you 2
    exp_growth If you deposit $4000 into an account paying 9% annual interest compounded monthly, how long until there is $10000 in the account?
  • Semiannually compound interest
    bank2 If you deposit $5000 into an account paying 8.25% annual interest compounded semiannually, how long until there is $9350 in the account?
  • Compound Interest
    exp_growth2 If you deposit $6000 in an account paying 6.5% annual interest compounded quarterly, how long until there is $12600 in the account?
  • RC time constant
    capacitor You introduced 1 Coulomb worth of electrons into the inner volume of a dielectric material with ϵr=6. Thirty minutes later, you found that only 36.79% of the electrons were in the internal volume. Determine the conductivity σ of the dielectric material.
  • Decibel
    tv By what percentage does the sound intensity increase if the sound intensity level increases by 1 dB?
  • Percentage increase
    exp_growth2 What is the annual percentage increase in the city when the population has tripled in 20 years?
  • 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 circus
    cirkus The arrival of the circus in Pilsen was seen in the morning at 08:00 by a city citizen. 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 at 08:
  • An investment
    exp_growth2 How long will it take for an investment to double at a simple interest rate of 5.10% per annum? Express the answer in years and months, rounded up to the next month.
  • Powers 3
    exp 2 to the power of n divided by 4 to the power of -3 equal 4. What is the vaule of n?
  • 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.
  • Intercept with axis
    log F(x)=log(x+4)-2, what is the x intercept
  • Geometric progression
    exp In geometric progression, a1 = 7, q = 5. Find the condition for n to sum first n members is sn≤217.
  • Water lilies
    lekno 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?
  • Exponential warm
    teplomer Suppose that a body with temperature T1 is placed in surroundings with temperature T0 different from that of T1. The body will either cool or warm to temperature T(t) after time t, in minutes, where T(t)=T0 + (T1-T0)e^(-kt) . If jello salad with 30 degree
  • Exponential equation
    exp 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?

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