# Logarithm - examples - page 2

1. Coordinate Determine missing coordinate of the point M [x, 120] of the graph of the function f bv rule: y = 5x
2. Car value The car loses value 15% every year. Determine a time (in years) when the price will be halved.
3. Lion or virgin We toss coin, every throw fits lion or a virgin with equal probability 1/2. Determine how much at least we have to make throws that with probability 0.9 lion fell at least once.
4. Log if ?, what is b?
5. Geometric sequence In the geometric sequence is a4 = 20 a9 = -160. Calculate the first member a1 and quotient q.
6. Logarithm Determine the number whose decimal logarithm is -3.8.
7. Log Calculate value of expression log |3 +7i +5i2| .
8. Gain Find the gain whenever the output power is 21x the input power.
9. Chebyshev formula To estimate the number of primes less than x is used Chebyshev formula: ? Estimate the number of primes less than 30300537.
10. The city 3 The city has 22,000 residents. How long it is expected to have 25,000 residents if the average annual population growth is 1.4%?
11. Exponential equation Solve for x: (4^x):0,5=2/64.
12. Photocopier 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?
13. Exponential equation Find x, if 625 ^ x = 5 The equation is exponential because the unknown is in the exponential power of 625
14. Exponential warm 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 degre
15. Geometric progression In geometric progression, a1 = 7, q = 5. Find the condition for n to sum first n members is: sn≤217.
16. 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.
17. Water lilies 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?
18. Intercept with axis F(x)=log(x+4)-2, what is the x intercept
19. Powers 3 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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