Logarithm - math problems

Number of problems found: 50

  • Logarithm
    log_hat Determine the number whose decimal logarithm is -3.8.
  • Seating rules
    school_class In a class are 24 seats but in 7.B class are only 18 students. How many ways can students sit? (The class has 12 benches. A bench is for a pair of students.) Result (large number) logarithm and thus write down as powers of 10.
  • Log
    log if ?, what is b?
  • 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?
  • Sequence
    seq Calculate what member of the sequence specified by (5n-2+15) has value 20.
  • Log
    exp_log Calculate value of expression log |3 +7i +5i2| .
  • Exp
    old_calculator If sqrt[7](202-122) = sqrt[n](256), then n is:
  • Exponential equation
    exp Solve for x: (4^x):0,5=2/64.
  • Radioactivity
    radioactivity After 548 hours decreases the activity of a radioactive substance to 1/9 of the initial value. What is the half-life of the substance?
  • Exponential equation
    exp In the set R solve the equation: ?
  • What is
    exp_growth2 What is the annual percentage increase in the city when the population has tripled in 20 years?
  • Intercept with axis
    log F(x)=log(x+4)-2, what is the x intercept
  • Gain
    solar Find the gain whenever the output power is 21x the input power.
  • Logarithmic equation
    nat_log_ln Solve equation: log13(7x + 12) = 0
  • Dice
    dices How many times must throw the dice, the probability of throwing at least one six was greater than 90%?
  • Car value
    car_old The car loses value 15% every year. Determine a time (in years) when its price will halve.
  • Compound interest
    exponential_usd Calculate time when deposit in the bank with interest 2.5% p.a. doubles.
  • Coordinate
    exp_ln Determine missing coordinate of the point M [x, 120] of the graph of the function f bv rule: y = 5x
  • Sum-log
    complex_log The sum of two numbers is 32, the sum of their logarithms (base 10) is 2.2. Determine these numbers.
  • 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.

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